A German newspaper that recently published controversial Charlie Hebdo cartoons depicting the Prophet Muhammad was targeted in an arson attack early Sunday morning.
Police told local media that "rocks and then a burning object" were thrown through windows of the Hamburger Morgenpost at around 2am local time. No one was injured, and authorities have reportedly taken two suspects into custody.
The paper confirmed via Twitter that its officers were attacked, writing "It's true: Tonight there was an arson attack targeting the editorial team."
The newspaper reprinted several Charlie Hebdo images Thursday with the headline "this much freedom must be possible."
Authorities told the German newspaper Deutsche Welle that it was "too soon" to determine if the arson was connected to the cartoons.
"Thick smoke is still hanging in the air, the police are looking for clues," the Hamburger Morgenpost wrote.
Several other German publications that reprinted the cartoons are now receiving police protection, the Associated Press reported. German Interior Minister Thomas de Maiziere cautioned all citizens to be wary of suspicious situations.
The French terror attacks that left 17 people dead have prompted heightened vigilance in France and across Europe. France's prime minister declared Saturday that the country was "at war" with radical Islam.
The attacks began Wednesday when brothers Said and Cherif Kouachi stormed the offices of satirical magazine Charlie Hebdo and fatally shot 12 people, including the editor, three cartoonists, and two policemen. The brothers then fled, prompting a massive manhunt across Paris.
Another gunman, Amedy Coulibaly, killed four people and took several hostages Friday at a kosher supermarket in Paris. Police eventually killed all three gunmen in standoffs Friday afternoon.
Police are still searching for accomplices to the terror attacks.
As many as a million people, including representatives from governments of Germany, Britain, Israel, and Palestine, gathered Sunday in Paris at a unity rally.
Follow Meredith Hoffman on Twitter: @merhoffman