Vilks was reported to be travelling in a civilian police vehicle which collided with a truck near the town of Markaryd in southern Sweden.
Investigators said the collision, which also killed two police bodyguards, showed no signs of foul play.
The 75-year-old artist had been living under police protection after receiving death threats over [a] cartoon.
The cartoon, published in 2007, offended many Muslims who regard visual representation of the Prophet as blasphemous. It came a year after a Danish newspaper published cartoons of the Prophet.
Since the publication of the cartoons, Vilks had been living under round-the-clock police guard following threats against his life.
In 2010, two men tried to burn down his house in southern Sweden.
In 2014, a woman from the US state of Pennsylvania pleaded guilty in a plot to kill him.
A year later, one person was shot dead by a lone gunman in Copenhagen, Denmark, at a meeting meant to mark the 25th anniversary of an Iranian fatwa against British writer Salman Rushdie, which Vilks attended. Vilks was widely seen as the intended target.
Police investigating the crash that killed the Swedish artist famous for drawing the Prophet Muhammad as a dog say a blown-out tire may be to blame.
Larks Vilks, 75, was killed at 3:30 p.m. on Sunday when his police escort vehicle collided head-on with a truck near Markaryd, southern Sweden. His two police chaperones also died.
Swedish police are still investigating the cause of the crash, and said Sunday they have no evidence suggesting the collision was intentional.
Stefan Sintéus, the head of the police investigations unit in southern Sweden, said Monday that the crash may have been caused by a tire blowing out on the police car, even though they were supposed to be puncture-proof, SVT News reported.
Breitbart finds some “Self-confessed Muslims” celebrating the death.
Vilks was an artist; the only cartoons by him seem to be Mohammed related.