A German newspaper that reprinted cartoons of the Prophet Mohammed from satirical magazine Charlie Hebdo has been targeted in an arson attack.

Hamburger Morgenpost, a regional tabloid in Hamburg, had splashed three cartoons on its front page after the deadly attack in Paris earlier this week.

The headline read: "This much freedom must be possible!"

A police spokesman, giving details of the attack, said: "Rocks and then a burning object were thrown through the window. Two rooms on lower floors were damaged but the fire was put out quickly."

No one was hurt in the attack, which happened around 1:20am Irish time.

"Thick smoke is still hanging in the air, the police are looking for clues," the newspaper said on its website.

Two men suspected of carrying out the attack were detained near the building, police said, without giving any further details.

The "key question" is whether there is a link between the Charlie Hebdo cartoons and the attack, a police spokesman told the AFP news agency, adding it was "too soon" to know for certain.

Reports said the newspaper's publishers had ordered private security for the building, which is in the western district of Othmarschen.

German news agency DPA said the attack was launched from a courtyard and hit the newspaper's archive room, destroying some records.

It is believed newspaper staff should be able to continue working there because the damage was relatively minor.

Charlie Hebdo, which has featured cartoons of the Prophet Mohammed in the past, was attacked by brothers Said and Cherif Kouachi on Wednesday.

The pair went on the run, before eventually being killed on Friday after a standoff with police.

A number of German newspapers have published the Charlie Hebdo cartoons on their front pages in a gesture of solidarity with the French cartoonists and in defence of freedom of speech.