See The Local (Denmark, English language) and Washington Post post tv. Heres an excerpt from BBC News:

Gunmen have killed one person and injured three police officers at a free speech debate in Copenhagen attended by a controversial Swedish cartoonist [Lars Vilks], officials say.

The French ambassador was also present at the seminar.

The debate, which took place in a cafe, was described on a personal website of Lars Vilks as a talk on whether any limits should be placed on artistic expression or freedom of speech.

A description of the event asked whether artists could dare to be blasphemous in the wake of the Charlie Hebdo terror attacks by Islamist gunmen in Paris last month.

Neither the cartoonist nor the ambassador appeared to be hurt. The BBC story also reports on many past attacks or attempted attacks on Vilks, who stoked controversy in 2007 by drawing pictures of the Prophet Muhammad dressed as a dog. Here is what appears to be one of those cartoons (copied from the Wikipedia site); apparently the picture is of a head, intended to be Muhammads, attached to a roundabout dog, a form of Swedish street sculpture sometimes put up by anonymous people in traffic roundabouts:

Lars Vilks cartoon of Muhammad as a roundabout dog (a form of Swedish street side sculpture).

Here is a statement from Danish Prime Minister Helle Thorning-Schmidt:

Denmark was today hit by a cold-blooded act of terror. Everything points toward the shooting in sterbro being a political assassination and thus an act of terror.

The shooting is an action that fills me with deep anger. We will do everything to find the guilty parties and bring them before a court.

The rest is here:

Volokh Conspiracy: Murder at Copenhagen debate on free speech attended by Swedish Muhammad cartoonist