Swedish cartoonist Lars Vilks, known for his derogatory depiction of the Muslim Prophet Muhammad, died in a car crash on Sunday afternoon, police said.
The vehicle with Vilks and two police officers aboard entered the opposite direction of the motorway before the collision, police said during a news conference about the accident.
Stefan Sinteus, head of the region's investigations unit, said that the reason why the vehicle went in the opposite direction was not clear yet, adding that: "The vehicle's tire may have burst because brake marks and fragmented tire remains were found at the scene."
"There is currently no indication that this is any form of attack," and there is nothing "indicating any external impact," he said.
Two police officers who had been assigned to protect him were also killed in the accident near the town of Markaryd in southern Sweden, local daily Dagens Nyheter reported.
The car carrying 75-year-old Vilks and the police officers collided with a truck and both vehicles caught fire, according to public broadcaster SVT.
The truck driver was injured.
Meanwhile, a Norwegian eyewitness told the Aftonbladet newspaper that he rushed for the first response after the accident and tried to extinguish the vehicles in fire.
"While the police car was driving in the opposite direction at a speed of almost 160 kilometers per hour (99.4 miles ph), its tire burst. The driver, who lost control, crashed into the truck coming from the opposite direction. Explosions occurred as a result of the crash. The truck and car caught fire. I especially wanted to respond to the burning car," the eyewitness said.
Vilks had been living under police protection since a controversial 2007 sketch due to death threats.
Police said they launched an investigation into the incident.
In 2007, Sweden's local newspaper Nerikes Allehanda published Vilks' cartoon insulting Prophet Muhammad. Since then, he had been living in a secret location with police guards.