A note about the Christchurch terror attacks was left at the scene of a mosque fire in California.
Police are investigating a fire at the Islamic Centre of Escondido as arson and a possible hate crime after a note was found that mentioned the two recent New Zealand terror attacks.
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CNN reports authorities got called at around 3:15am on Sunday to a fire in the town north of San Diego.
Several people at the mosque came outside and extinguished the fire before authorities arrived, said Lt. Chris Lick of Escondido police.
Police said they don't currently have a suspect.
Lick said he would not be disclosing what the note said, but "it was a reference to the New Zealand shooting".
"Everybody should remain absolutely vigilant and watchful over their prayer centres."
A member of the Escondido Islamic community, Yusef Miller, encouraged Muslims to be careful at this time.
"It was especially alarming to have it happen this morning, and everybody is on edge here today."
Miller told the Washington Post that mosque attendees were "very on edge", but that wouldn't stop them from attending the mosque.
"We won't stop praying... we won't stop gathering."