Bryant (41) rocketed to fame as an 18-year-old rookie and played 20 years for the Los Angeles Lakers, 18 as an all-star forward, and won five NBA championships.
The cause of the crash on Sunday morning (local time) was unknown, and an investigation by the Federal Aviation Administration and the National Transportation Safety Board could take months.
Bryant was known since his playing days to travel frequently by helicopter to avoid the Los Angeles area's notorious traffic.
His Sikorsky S-76 craft went down in low clouds and foggy weather shortly before 10am in hilly terrain just outside Calabasas, California, about 65km northwest of central Los Angeles, sparking a brush fire, officials said.
"There were no survivors," county sheriff Alex Villanueva told a news conference, saying the flight manifest showed nine people on board. He declined to identify them.
NBA Commissioner Adam Silver confirmed that Bryant and his daughter Gianna (Gigi) were among those killed, and sent condolences to Bryant's wife, Vanessa.
"He was one of the most extraordinary players in the history of our game, with accomplishments that are legendary," Silver said, as tributes poured in from players, politicians and entertainers.
The fire and debris field from the crash spread over steep terrain in the grass-covered foothills of the Santa Monica Mountains, county Fire Chief Daryl Osby said.
Others on board besides the pilot were a teammate from Bryant's daughter's basketball squad and a parent of the teammate, NBC News reported.
Orange Coast College baseball coach John Altobelli was also one of the victims, the Orange County Register said, citing assistant coach Ron La Ruffa.
Weather was likely to figure prominently in the crash investigation. Fog in the area was so bad that the Los Angeles Police Department had grounded its helicopter fleet on Sunday morning, the Los Angeles Times and CNN reported.
His death has sent shockwaves through the National Basketball Association, which he helped propel to international prominence, and stunned fans around the world.
"The NBA family is devastated by the tragic passing of Kobe Bryant and his daughter, Gianna," NBA commissioner Adam Silver said in a statement. "For 20 seasons, Kobe showed us what is possible when remarkable talent blends with an absolute devotion to winning."
Jerry Kocharian was standing outside the Church in the Canyon drinking coffee when he heard a helicopter unusually low struggling overhead."It (didn't) sound right and it was real low. I saw it falling and spluttering. But it was hard to make out as It was so foggy," Kocharian said. The helicopter vanished into a cloud of fog and then there was a boom.
"There was a big fireball," he said. "No one could survive that."
The crash occurred shortly before 10am near Las Virgenes Road, south of Agoura Road.
Allen Kenitzer, an FAA spokesman, said his agency and the National Transportation Safety Board were investigating.
'KOBE WE LOVE YOU'
Reaction to Bryant's death was swift, and moments of silence were observed before some of Sunday's NBA games.
In San Antonio, the Toronto Raptors and San Antonio Spurs allowed the 24-second shot clock to expire on each of their first possessions, in tribute to Bryant's jersey number, 24.
"I am in shock over the tragic news of Kobe's and Gianna's passing. Words can't describe the pain I'm feeling," said Michael Jordan, who won six NBA championships with the Chicago Bulls.
"Kobe was an amazing dad who loved his family deeply - and took great pride in his daughter's love for the game of basketball."
Former US president Barack Obama tweeted: "Kobe was a legend on the court and just getting started in what would have been just as meaningful a second act. To lose Gianna is even more heartbreaking to us as parents. Michelle and I send love and prayers to Vanessa and the entire Bryant family on an unthinkable day."
"This is a moment that leaves us struggling to find words that express the magnitude of shock and sorrow we are all feeling right now, and I am keeping Kobe's entire family in my prayers at this time of unimaginable grief," Los Angeles Mayor Eric Garcetti said in a statement.
Stunned fans gathered near the Lakers' home arena, the Staples Center in downtown Los Angeles, surrounding a wreath with the message: "Kobe we love you RIP."
Some in the crowd dabbed tears as others laid flowers and basketball sneakers at the wreath. Fans wore both his No 24 and No 8 jerseys, breaking the sombre mood with occasional chants of "Kobe, Kobe."
Hours later, inside the arena, musicians and performers paid tribute to Bryant from the stage of the Grammy Awards.
One of a handful of internationally recognised athletes known simply by their first names, Bryant was an avid supporter of football and women's basketball.
He spoke Spanish as well as Italian, having spent part of his youth in Italy, where his father, former NBA player Joe "Jellybean" Bryant, played several seasons professionally.
He also won an Oscar in 2018 as writer-producer of that year's best animated short film, Dear Basketball, which Bryant also narrated, and he sometimes mingled with show-business stars in Los Angeles.
'MUCH MORE THAN AN ATHLETE'
"Most people will remember Kobe as the magnificent athlete who inspired a whole generation of basketball players. But I will always remember him as a man who was much more than an athlete," Kareem Abdul-Jabbar, the all-time NBA scoring leader and former Laker, said on Twitter.
Bryant was accused of sexual assault in 2003 by a woman who worked at a Colorado hotel, tarnishing his reputation and setting off a media storm over the case. Bryant denied the accusations, and charges eventually were dismissed after his accuser refused to testify.
Bryant and his wife filed for divorce in 2011 after 10 years of marriage, but the couple said in 2013 they had reconciled.
Besides Gianna, they had three other daughters: Natalia, Bianca and Capri, who was born in June 2019.
Bryant, who played all 20 of his NBA seasons with the Lakers, also won two Olympic gold medals as a member of the US men's basketball team in 2008 and 2012.
Nicknamed "The Black Mamba," he became eligible to enter the Hall of Fame this year and is certain to be selected when the 2020 class is enshrined.
Bryant demonstrated from an early age he would surpass the accomplishments of his father, who played eight seasons in the NBA.
The Philadelphia native went straight from high school to the NBA, skipping the college ranks. Since he was just 17 at the time, his parents needed to co-sign his first contract with the Lakers. He played his first game with the team soon after turning 18 in 1996.
He was the third-leading scorer in league history with 33,643 points, until LeBron James surpassed him on Saturday.
In his final tweet, Bryant saluted James' achievement, writing: "Continuing to move the game forward @KingJames. Much respect my brother."
Kobe Bryant excelled at Lower Merion High in Ardmore, Pennsylvania, near Philadelphia, winning numerous national awards as a senior before announcing his intention to skip college and enter the NBA draft.
He was selected 13th overall by Charlotte in 1996, but the Los Angeles Lakers had already worked out a deal with the Hornets to acquire Bryant before his selection. Bryant impressed Lakers General Manager Jerry West during a pre-draft workout session in Los Angeles.
Less than three weeks later, the Lakers traded starting centre Vlade Divac to the Hornets in exchange for Bryant's rights. Bryant, whose favourite team growing up was the Lakers, had to have his parents co-sign his NBA contract because he was 17 years old.
The 6ft, 6in (198cm) guard made his pro debut in the 1996-97 season opener against Minnesota; at the time he was the youngest player ever to appear in an NBA game. He started in only a handful of games during his rookie season, coming off the bench in support of Nick Van Exel and Eddie Jones.
However, coach Del Harris played him more as the season progressed, allowing Bryant to showcase the skills that made him a top candidate for rookie of the year. Those skills were also on display when Bryant won the 1997 NBA slam dunk competition.
Bryant continued to improve during his sophomore season in the league, averaging 15.4 points per game. However, his breakout came in the lockout-shortened 1998-99 season when he started in all 50 games after the Lakers traded away Van Exel and Jones.
Bryant and leading scorer Shaquille O'Neal quickly morphed into one of the most lethal scoring and defensive combinations in the league. Together, with coach Phil Jackson guiding them, they led the Lakers to three consecutive championships (2000-02) as Bryant began to cement his place as the game's top player.
Despite coming together to win some of the most closely fought playoff series in Lakers history, friction started to develop between Bryant and O'Neal.
Tension between the two stars continued to build during the 2002-03 and 2003-04 seasons as the Lakers failed to capitalise on their status as top contenders for the NBA title. Making matters worse, Bryant was arrested in July 2003 on allegations of sexual assault. The charges were eventually dropped, but Bryant's reputation took a hit.
After the Lakers lost to Detroit in the NBA Finals with a star-studded team that included Karl Malone and Gary Payton, O'Neal was traded to Miami and Jackson's coaching contract was not renewed. As the team's undisputed leader, Bryant signed a seven-year contract to remain with the team.
Bryant summed up the tensions between him and O'Neal after the Lakers won the NBA title in 2009: "We're great as individuals, but ... it's probably the first dynamic duo that had two alpha males on one team. We managed to make it work for three championships."
Bryant posted some of the best offensive numbers of his career over the next three seasons, but the team struggled, failing to make the playoffs in 2005 before suffering consecutive first-round defeats to Phoenix in '06 and '07. Jackson returned to the team for the 2005-06 season, and Bryant went on to lead the league in scoring that season with a career-best 35.4 average.
He scored 40 points or more in 27 games and became the first player since Wilt Chamberlain in 1964 to finish with 45 points or more in four consecutive games. His biggest single-game achievement came January 22, 2006, against Toronto when he scored a career-high 81 points, second most in NBA history.
Earlier that season, on December 20, 2005, he scored 62 points in 33 minutes through three quarters of a game against Dallas; he had outscored the entire Mavericks team, 62-61, entering the final quarter, in which Bryant did not play. Bryant continued to impress during the 2006-07 season, scoring 50 or more points in a team-record 10 games and averaging 31.6 points a game to capture his second NBA scoring title.
Bryant's 2007-08 NBA MVP season got off to a tumultuous start after he reportedly demanded to be traded. He was reportedly unhappy with Lakers General Manager Mitch Kupchak and Jackson."I would like to be traded," Bryant said during a radio interview.
"Tough as it is to come to that conclusion, there's no other alternative. It's rough, man, but I don't see how you can rebuild that trust. I just don't know how you can move forward in that type of situation."
Bryant eventually backtracked on his trade demands and posted perhaps his best all-around season, leading a team re-energised by Pau Gasol's arrival from Memphis in February 2008 to a first-place finish in the Western Conference.
The Lakers embarked on a memorable playoff run before losing to Boston in the Finals. Later that year Bryant went on to win a gold medal with the US team at the 2008 Summer Olympic Games in Beijing.
With Bryant pleased about the direction the team was heading, he guided the Lakers to back-to-back titles in 2009 and 2010. He was named the NBA Finals MVP both years as the team once again ascended to the top of the NBA.
Ongoing soreness in Bryant's knee and ankle coupled with the team's heavy reliance in him played a role in the Lakers' championship run coming to an end in 2011. Bryant posted his lowest points per game totals since the 2003-04 season as he dealt with the aftereffects of off-season arthroscopic knee surgery.
He went on to win his fourth NBA All-Star Game most-valuable-player award but fell short of his ultimate goal of winning a sixth NBA title. Bryant also became the youngest player in NBA history to amass 27,000 career points.
Bryant finished third in league scoring in 2011-12 despite dealing with ongoing knee and ankle issues. In January 2012, he scored at least 40 points in four consecutive games, which included a 48-point effort against the Phoenix Suns.
But Bryant's season came to a disappointing end when he suffered a torn Achilles' tendon against the Golden State Warriors on April 10. The injury and subsequent surgery prevented Bryant from playing in the early portion of the 2013-14 season.
Bryant, who signed a two-year, $US48.5 million ($NZ73.7 million) contract extension with the Lakers before the start of the 2013-14 season, did not return from injury until December.
He played in only six games before suffering a lateral tibial plateau fracture in his left knee. The injury forced him to miss the remainder of the season as the Lakers limped to a 27-55 record, missing the playoffs for only the second time since Bryant joined the franchise.
He retired from the NBA but began a new career in Hollywood. In 2018, he won an Oscar along with director Glen Keane for the animated short film Dear Basketball.
Just last night, Laker LeBron James passed Bryant for third on the NBA's all-time scoring list.
- Reuters and TNS
