One civilian was killed and three police were wounded on Saturday in shooting at a public meeting in the Danish capital Copenhagen attended by the controversial Swedish artist Lars Vilks, police and the Danish Ritzau news agency reported.
Danish police confirmed one civilian had been killed in a shooting and said the suspects had fled in a car.
Ritzau said both Vilks and the French ambassador, who was also attending, were both unharmed, but that three police had been wounded. The gathering was billed as a debate on art and blasphemy.
Just over a month ago, 17 people were killed in France in three days of violence that began when two Islamist gunmen burst into the Paris offices of the satirical weekly Charlie Hebdo, opening fire in revenge for its publication of satirical images of the Prophet Mohammad.
Vilks stirred controversy in 2007 with published drawings depicting Mohammad as a dog which sparked threats from Islamist militant groups.
He has received numerous death threats and has lived under constant protection by the Swedish police since 2010. Two years ago, an American woman who called herself Jihad Jane was sentenced to 10 years in prison for plotting to kill him.
French President Francois Hollande said Interior Minister Bernard Cazeneuve would go to Copenhagen as soon as possible.