Lars Vilks, whose cartoons of Prophet Muhammad resulted in worldwide protests has reportedly died in a road accident in southern town of Markaryd, Sweden.
The 75-year-old artist was living under police protection since the controversial drawings were published in 2007.
According to reports, he was travelling in a police vehicle which collided with a truck.??
"This is a very tragic incident. It is now important to all of us that we do everything we can to investigate what happened and what caused the collision," Swedish police said in a statement on Monday.
"Initially, there is nothing that points to anyone else being involved."
Two police officers were also killed.
The cartoons were controversial because most Muslims across all sects consider any depiction of the Holy Prophet as offensive.
He was threatened by some groups with a bounty on his head, which resulted in a strict police protection for him. His house was also fire-bombed.
According to Reuters, in 2015, one person was killed 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?had said that the cartoons were not intended to provoke Muslims, but to challenge political correctness in the art world.
With inputs from Reuters?