A person of interest was detained in connection with a fire that burned a mosque in a desert city east of Los Angeles. Authorities believe the fire was an "intentional act."
Details about the person of interest weren't immediately available.
The case is being investigated as a possible hate crime, according to the Riverside County Sheriff's Department.
The fire was reported around noon at the Islamic Society of the Coachella Valley at 84650 Avenue 49.
Deputy Armando Munoz, of the Riverside County Sheriff's Department, confirmed that authorities believe someone intentionally set the fire.
The flames were contained to the front lobby of the 1,800-square-foot building, but there was smoke damage throughout the structure, officials said. Video showed damage to the building's entrance.
A man who was inside the building with at least three others said he heard an explosion before the fire.
"It was big flames for just a couple seconds, but not a short circuit, accidental like that," he said.
No injuries were reported. A bomb squad was called in to investigate, as well as the FBI.
"I'm really upset that somebody would do something like this," Alisa Shabazz said.
Shabazz is a member of Islamic Society of the Coachella Valley, which she has attended every Friday for more than 25 years. Shabazz said if the fire happened later when the mosque has it's 1 p.m. prayer service, it would have been full of people.
"We're peaceful people. We don't terrorize people. We don't bomb people. I've been a muslim all my life I never had to deal with this," Shabazz said.
The mosque is located about 75 miles from the site of the mass shooting in San Bernardino. Witnesses feared the fire may somehow be in retaliation for the massacre carried out by husband and wife Islamic extremists.
"If in fact as it appears to be potential act against this church for reasons of religion, I would think that is terrorism, and terrorism is terrorism no matter whether it's like what we saw in San Bernardino or someone who reacts, they're both terrorists," Riverside County Supervisor Jon Benoit said.
Witnesses said that investigators at the scene told them the fire was intentionally set. Mohammed Aowishah, who attends the mosque, said several people were inside the building at the time.
"We feel bad," said Mohammed Aowishah, who attends the mosque. "We didn't do anything. We are innocent people."
NBC4 has reached out to the Council on American-Islamic Relations for comment on the fire.
In November 2014, six rounds were fired at the mosque -- three struck a car in front of the building, two hit the building and one struck a fence. No injuries were reported.
The mosque has been at the Coachella Valley location for more than 15 years.
A press conference was scheduled for Saturday at noon with local law enforcement.
Tony Shin contributed to this report.