Police are investigating a possible arson attack at a Southern California mosque Sunday, CBS affiliate KFMB-TV reported. A small fire was reported early Sunday at the Islamic Center of Escondido, some 30 miles north of downtown San Diego.

Police said the fire caused damage to the mosque's exterior and when crews arrived, they found graffiti with a hate message spray painted on a wall. Investigators will also be looking into the incident as a possible hate crime.

KFMB-TV said police confirmed the graffiti referenced the terrorist attack in Christchurch, New Zealand, that killed 50 people at two separate mosques earlier this month.

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There were no reports of anyone injured or immediate word on any suspects. Seven people were inside the building when they noticed the fire, Escondido Police Lt. Chris Lick said. KFMB-TV said they were able to get the blaze out with a fire extinguisher and called 911. Nobody saw who set the fire.

Damage to an exterior wall of the Islamic Center of Escondido can be seen on the left side of this photo. KFMB-TV

There was a vigil planned Sunday night at the mosque. Organizers said community members would be speaking followed by Muslim prayer. A silent vigil will continue after that, KFMB-TV reported.

"Our message to community is to make sure they keep a watchful eye out," Lick said. "If they see something suspicious, especially around a house of worship, they should call police."

Federal agents from the FBI and Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) are helping with the investigation, according to police.

The Associated Press obtained a statement from Dustin Craun, the head of the Council of American-Islamic Relations in San Diego, in which it said his civil rights group stands with the mosque.

"It is disturbing enough that some sick individual would attempt to burn a house of worship to the ground, but referencing the slayings in New Zealand is beyond the pale," the statement read. "While the majority of humanity has responded to the tragedy to draw closer to one another and refute hatred, a violent and hate-filled minority seeks further divisions. We are grateful that someone was inside the mosque and was able to act quickly to put the fire out. We ask anyone with information to come forward and contact the Escondido Police Department. We stand in solidarity with our community members who attend the Islamic Center of Escondido."