French police shot dead a man holding a knife who tried to enter a police station, according to police union sources.

A sheet of paper showing the Islamic State flag and claims of responsibility written in Arabic were found on the man, the Paris prosecutor said in a statement.

“A mobile phone and a piece of paper, on which appear the Daesh flag and a clear written claim in Arabic, were found on the individual,” Francois Molins said, referring to the Arabic acronym for Islamic State.

One of the sources said the man appeared to be wearing a belt of some sort, but could not say whether it was an explosive one, as Reuters reports.

Eyewitnesses said two or three shots were heard and that the man entered the police station shouting ‘Allahu Akbar’.

Journalist from the New York Times Anna Polonyi published a photo of a man lying on the ground outside the building. She said a robot appears to be inspecting the body.

The incident occured as Paris marks the first anniversary of the Charlie Hebdo attacks, on January 7, 2015, which killed 12 people