Forensic investigators are seen at the site of a shooting in Copenhagen, February 14, 2015. A civilian was killed and three police were wounded on Saturday in a shooting at a meeting in Copenhagen attended by Lars Vilks, an artist who has received death threats since publishing images of the Prophet Mohammad. Danish police confirmed one civilian had been killed in the shooting and said the two suspects had fled in a car after the attack on the gathering, which had been billed as a debate on art and blasphemy. [Photo/Agencies]

COPENHAGEN - A civilian was killed and three police wounded on Saturday when a masked gunman sprayed bullets into a Copenhagen meeting attended by a Swedish artist threatened with death for his cartoons of the Prophet Mohammad.

Prime Minister Helle Thorning-Schmidt said Denmark was on high alert after a "terrorist attack" police said was aimed at artist Lars Vilks, who stirred controversy in 2007 with published drawings depicting the Prophet Mohammad as a dog.

The attacker escaped in a car that was found later in the outskirts of Copenhagen. Danish police were put on high alert.

The cafe complex was hosting a cultural event called "Art, Blasphemy and Freedom of Expression". French ambassador to Denmark Francois Zimeray, who was attending the event, likened the shooting to the attack on the Charlie Hebdo newspaper in Paris by Islamist militants that killed 12 people last month.

"We feel certain now that it was a politically motivated attack, and thereby it was a terrorist attack," Thorning-Schmidt told journalists close to the site of the attack.

European Council President Donald Tusk called the attack "another brutal terrorist attack targeted at our fundamental values and freedoms, including the freedom of expression."

The event's main speaker was Vilks. He and Zimeray were unharmed.

Witnesses said one or more gunmen had tried to shoot their way into the venue before guards returned fire.

"I heard someone firing with automatic weapons and someone shouting. Police returned the fire and I hid behind the bar. It felt surreal, like in a movie," Niels Ivar Larsen told Danish TV2.

The police said at first they were seeking two men who had sped off in a getaway vehicle, but later said they were looking for one man and issued a photograph of a suspect wearing a thick coat and maroon bobble hat. His face was obscured by a scarf.

"I'm still a bit stunned. I was inside, I had just sat down after my speech and then I heard shots," Zimeray told French news channel TF1.

"We all dove to the floor as we heard the gunshots and tried to protect ourselves, and we crawled to the emergency exit."