One man is dead and three policemen have been wounded in a shooting at a freedom of speech event attended by an artist who drew a controversial cartoon of the Prophet Mohammed, police said.

Swedish cartoonist and historian Lars Vilks, who depicted the key Islamic holy figure with the body of a dog in 2007, was at the Krudttonden cafe in Copenhagen, Denmark, when shots were fired around 4pm yesterday.

The cafe in northern Copenhagen was hosting an event titled 'Art, Blasphemy And The Freedom Of Expression'.

Danish prime minister Helle Thorning-Schmidt said: "We feel certain now that it's a politically motivated attack, and thereby it is a terrorist attack.

"We take this situation extremely seriously. We are in a high alarm all over the country, and our main priority at this stage is to catch the perpetrators and make sure that we find them as soon as possible."

Danish police, who initially said they were searching for two suspects, issued a picture of the main suspect last night, taken on street cameras near to where the getaway car, a VW Polo, was later found dumped.

The shooting comes little more than a month after the attack on the offices of the French satirical magazine Charlie Hebdo in Paris which left 12 people dead.

French president Francois Hollande expressed his solidarity with Danish Prime Minister Helle Thorning-Schmidt.

In a statement issued from his official Twitter account Hollande also said Interior Minister Bernard Cazeneuve would go to Copenhagen as soon as possible.

French Foreign Minister Laurent Fabius condemned what he called a "terrorist attack" in a separate statement.

Prime Minister David Cameron said his thoughts were with the Danish people, tweeting: "I condemn the shootings in Copenhagen. Freedom of speech must always be protected."

Copenhagen Police said both Vilks and French ambassador to Denmark Francois Zimeray, who was also at the event, were both unharmed.

Zimeray tweeted from his @FranceDK account shortly after the shooting, writing: "Still alive in the room."

He later said: "They fired on us from the outside. It was the same intention as (the January 7 attack on) Charlie Hebdo except they didn't manage to get in.

"Intuitively I would say there were at least 50 gunshots, and the police here are saying 200.

"Bullets went through the doors and everyone threw themselves to the floor."

In an audio recording which emerged from the attack, one of the speakers at the debate is suddenly interrupted by a barrage of gunshots.

Niels Ivar Larsen, who was speaking at the event, told how he was forced to take shelter as the gunmen fired indiscriminately at the cafe.

He said: "I heard someone firing with an automatic weapons and someone shouting.

"Police returned the fire and I hid behind the bar. I felt surreal, like in a movie."

Police said the perpetrators fled in a dark coloured VW Polo car and warned the public not to approach the vehicle or driver.

One of the organisers of the event, Helle Merete Brix, said she "saw a masked man running past" during her ordeal.

Speaking afterwards she said: "I clearly consider this as an attack on Lars Vilks."

Vilks, 68, outraged many Muslims in 2007 after he depicted the prophet Muhammad's head on the body of a dog.

In September that year, Vilks had a $100,000 bounty placed on his head by the al-Qaeda faction in Iraq in response to his drawings.

The controversial cartoonist has received numerous death threats since and has lived under the constant protection of the Swedish police since 2010.

In an interview with Associated Press in 2010, Vilks defended his work and insisted he was not deliberately trying to offend Islam.

He said: "As an artist, you have to take a stand for things. If you do something, you have to take full responsibility for it.

"I'm actually not interested in offending the prophet. The point is actually to show that you can. There is nothing so holy you can't offend it."

Jodie Ginsberg, the chief executive of Index on Censorship, condemned the attack, saying: "The use of violence on a gathering exploring the intersection of religious and artistic freedom should send shivers down our spines.

"The Charlie Hebdo murders inspired intensified public debate about free speech and its value. Many people who had previously given little thought to free speech were drawn for the first time into online discussions or attended events to help them get a better understanding of the issues. It would be terrible if violent acts such as that in Copenhagen shut down free speech even further.

"The ability to express ourselves freely, to attend meetings and debates without fear of violence, is fundamental to a free society. Free speech must be protected."