At the beginning of the battle that has raged for the past 12 days in Marawi City at the southern end of the Philippines, dozens of Islamist militants stormed its prison, overwhelming the guards.
"They said 'surrender the Christians'," said Faridah P. Ali, an assistant director of the regional prison authority. "We only had one Christian staff member so we put him with the inmates so he wouldn't be noticed,” he said.
Fighters from the Maute group, which has pledged allegiance to Islamic State (IS), menaced the guards and shouted at prisoners: but no one gave up the Christian man. "When they freed the inmates, he got free," said Ali.
It was a brief moment of cheer, but over the next few hours the militants took control of most of the city, attacked the police station and stole weapons and ammunition, and set up roadblocks and positioned snipers on buildings at key approaches. The assault has already led to the death of almost 180 people and the vast majority of Marawi's population of about 200,000 has fled.
The seizing of the city by Maute and its allies on the island of Mindanao is the biggest warning yet that the Islamic State is building a base in Southeast Asia and bringing the brutal tactics seen in Iraq and Syria in recent years to the region.
Defense and other government officials from within the region told Reuters evidence is mounting that this was a sophisticated plot to bring forces from different groups who support the Islamic State together to take control of Marawi.
The presence of foreigners - intelligence sources say the fighters have included militants from as far away as Saudi Arabia, Pakistan, Chechnya and Morocco - alongside locals in Marawi, has particularly alarmed security officials.
For some time, governments in Southeast Asia have been worried about what happens when battle-hardened Islamic State fighters from their countries return home as the group loses ground in the Middle East, and now they have added concerns about the region becoming a magnet for foreign jihadis.
"If we do nothing, they get a foothold in this region," said Hishammuddin Hussein, the defence minister of neighbouring Malaysia.
Defence and military officials in the Philippines said that all four of the country’s pro-Islamic State groups sent fighters to Marawi with the intention of establishing the city as a Southeast Asian ‘wilayat’ – or governorate - for the radical group.
Mindanao - roiled for decades by Islamic separatists, communist rebels, and warlords – was fertile ground for Islamic State's ideology to take root. This is the one region in this largely Catholic country to have a significant Muslim minority and Marawi itself is predominantly Muslim.
It is difficult for governments to prevent militants from getting to Mindanao from countries like Malaysia and Indonesia through waters that have often been lawless and plagued by pirates.
The Combating Terrorism Center, a West Point, New York-based think tank, said in a report this week that Islamic State is leveraging militant groups in Southeast Asia to solidify and expand its presence in the region. The key will be how well it manages relations with the region’s jihadi old guard, CTC said.
"PEOPLE WILL GET KILLED"
Officials in neighbouring Indonesia worry that even if the Filipinos successfully take back Marawi in coming days, the threat will still remain high.
“We worry they will come over here,” said one Indonesian counter-terrorism official, noting that Mindanao wasn’t very far from the Indonesian island of Sulawesi.
More than 2000 people remain trapped in the centre of Marawi, with no electricity and little food and water. Some are pinned down by the crossfire between the military and the militants, while others fear they will be intercepted by the militants as they flee, according to residents.
The bodies of eight labourers who had been shot in the head were found in a ravine outside Marawi last Sunday. The police said they had been stopped by the militants while escaping the city.
There will most likely be more civilian casualties in retaking the city, the military said.
"We are expecting that people will get starved, people will get hurt, people will get killed," said Herrera, the military spokesman. "In these types of operations, you can't get 100% no collateral damage."
