Police are urging southern drivers to slow down and lay off the alcohol, saying "your life literally depends on it".
In the latest fatality on southern roads, one person was found deceased following a single-vehicle crash in Glassford Rd, near Omakau, about 11pm on Thursday night.
On Monday night a motorbike rider was found in a critical condition in Bannockburn Rd and later died at the scene.
No other vehicles were involved in the crash.
One person was left dead and two seriously injured after their vehicle rolled at Quarry Hills in Southland last Saturday night.
The horror run started with a two-vehicle crash involving a ute and a motorcycle on State Highway 8 in the Cromwell Gorge on Wednesday last week.
The motorcyclist and the ute driver were both critically injured and later died at the scene.
A second person in the ute survived the crash and was treated at Dunstan Hospital.
Southern district road policing manager Inspector Craig Brown said police had noticed three factors in recent serious and fatal crashes — speed, poor decision-making and driving while impaired by the likes of alcohol.
"Our hearts go out to the families of those involved. They’re forced to face the devastating consequences of these crashes, which potentially could have been avoided.
"These crashes have a ripple effect in the community, affecting other motorists, witnesses and the people who are first on the scene.
"Every fatal crash also has an impact on attending emergency services personnel."
While police were out on the roads carrying out enforcement around excess speed, impairment, restraints and distraction everyone had to take responsibility to avoid road deaths.
"We are urging members of the public to take road safety seriously, slow down, don’t drive impaired and make good judgement calls — your life literally depends on it."
Anyone seeing unsafe driving on the road should contact police as soon as possible, Insp Brown said.
Police have not released the names of the people involved in the fatalities. All the deaths have been referred to the coroner.
