(AP) STOCKHOLM -- A Swedish artist who angered Muslims by depicting the Prophet Muhammad as a dog was assaulted Tuesday as furious protesters interrupted his university lecture about the limits of free speech.
Lars Vilks told The Associated Press a man leaped from the front row and head-butted him as he was delivering his lecture at Uppsala University, breaking Vilks' glasses but leaving him uninjured.
Police later said the attacker was stopped before he could reach Vilks and that the artist may have bumped into plain-clothes officers who briskly evacuated him from the room. Three people were detained, but it wasn't immediately clear whether the attacker was among them.
A video clip of the incident by a Swedish newspaper showed police using pepper spray and batons to hold off an angry crowd shouting "God is great" in Arabic after Vilks was escorted out of the lecture hall.
WATCH THE INCIDENT
Vilks has faced numerous threats over his controversial drawing of Muhammad with a dog's body, but Tuesday's incident was the first physical assault directed against him.
Earlier this year U.S. investigators said Vilks was the target of an alleged murder plot involving Colleen LaRose, an American woman who dubbed herself "Jihad Jane," and who now faces life in prison. She has pleaded not guilty.
Vilks said a group of about 15 people had been shouting and trying to interrupt the lecture before the incident at the university in Uppsala, about 40 miles (70 kilometers) north of Stockholm.
Some of them stormed toward the front of the room after the attack and clashed with security guards as Vilks was pulled away into a separate room, he said, describing the scene as "complete chaos."
"A man ran up and threw himself over me. I was head-butted and my glasses were broken," Vilks said before hanging up for questioning by police.
Uppsala police spokesman Jonas Eronen later said that the attacker was stopped by officers before he could get to Vilks. The physical contact Vilks described probably happened when police in civilian clothes evacuated the artist "in a brusque manner," Eronen said.
A man and a woman were detained on suspicion of violence against police while another man was held for disturbing public order, he said. All were just under 20 years old.
Uppsala University spokeswoman Pernilla Bjork said Vilks was showing an excerpt from a film by an Iranian artist about Islam and homosexuality that had been banned from YouTube when the commotion started.
"It was about when Muslims and Muhammad are represented in homosexual situations," said Anders Montelius, a 23-year-old student who attended the lecture.
"Some people started shouting, things happened really fast. About 10-15 seconds later it erupts. A guy from the front row gets up and sets upon Vilks. Several others followed this man. There was commotion and police pepper-sprayed a couple of people," Montelius told AP.
"When the university person responsible for the lecture announced that the lecture was discontinued, there were cheers and chants in Arabic," he said.
The video posted on the Web site of newspaper Uppsala Nya Tidning showed agitated police officers clashing with protesters at the front of the lecture hall. A female police officer uses pepper spray to subdue a young man. Another youngster is wrestled to the ground.
University officials said there had been a peaceful demonstration by Muslims outside the university before Vilks started to speak, and that about 260 people attended his lecture. Bjork said the university had been in contact with police and security guards before Vilks' lecture to ensure his safety.
"We think it is our task as a university to be able discuss difficult issues," she said. "We think it is very unfortunate that this has resulted in violence."
Vilks made his rough sketch more than a year after 12 Danish newspaper cartoons of the prophet sparked furious protests in Muslim countries in 2006.
A Swedish newspaper printed the drawing, leading to further protests, and revived a heated debate in the West and the Muslim world about religious sensitivities and the limits of free speech.
It also led to numerous death threats against Vilks, who was temporarily moved to a secret location after al-Qaida in Iraq put a $100,000 bounty on his head in September 2007.
Associated Press Writer Karl Ritter contributed to this report.