Graffiti left after an alleged arson attack at a California mosque referenced the Christchurch terror attack in which 50 Muslim people were gunned down on March 15.
A fire broke out around 3am Sunday at the Islamic Center of Escondido, located roughly 50km north of San Diego, NBC reported.
People inside the mosque were able to put the fire out before firefighters arrived. There was visible scorching to one side of the mosque, NBC reported.
Police said the suspect left a note in the mosque's parking lot referencing the New Zealand attacks.
The FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives are investigating the incident along with local police, but no arrests have been made so far.