A multi-agency investigation was underway Saturday following a four-alarm fire that caused “extensive damage” to the historic 249-year-old San Gabriel Mission, authorities said.

The blaze at 4:25 a.m. sent firefighters to 428 S. Mission Road, where the first to arrive reported a large column of smoke and flame coming from the corner of the roof, said Capt. Antonio Negrete of the San Gabriel Fire Department.

“During the course of the fire, portions of the roof fell upon the firefighters,” Negrete said. “They were evacuated and initiated a defensive fire attack.”

The fire was knocked down at 6:48 a.m., he said. No injuries were reported.

“It’s a tragic loss for our city. It’s our city identifier,” Negrete said. “We’re trying to cope with it.”

The entire wood roof was gone, and the building sustained “extensive damage,” including destruction of pews, he said, although the altar area was saved.

Negrete told the Los Angeles Times that the bell tower and museum remained intact.

On Saturday afternoon, investigators from the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives and a regional task force including San Gabriel, Monterey Park, Monrovia and San Marino investigators were busy in the front of the mission where the fire was believed to have started, Negrete said. They could not get farther back because firefighters were still putting out hot spots, he said.

A dog from the Los Angeles Fire Department was also on the scene sniffing to see if any accelerants were used to start the fire, Negrete said. A report on the cause was not expected for a week.

The San Gabriel Fire Department said the initial investigation showed no immediate sign of arson.

“We need to be diligent in our investigation and check all of the boxes,” Negrete said. While arson investigations are routine with all fires at houses of worship, Negrete noted that this blaze came at a time of criticism of the California missions and damage to several statues of Franciscan Father Junipero Serra.

This particular mission was founded by Serra in 1771 in San Gabriel, a few miles southeast of Pasadena.

Church staff removed a statue of Serra from public view last week and put it in safe storage, Negrete said.

Robert Barron, auxiliary bishop of the Archdiocese of Los Angeles, tweeted: “Friends, I was deeply troubled to learn that the historic San Gabriel Mission church in Los Angeles was seriously damaged by a fire early this morning. The Archbishop of Los Angeles is on the scene.”

Archbishop Jose Gomez tweeted photos from the scene a short time later.

“Our beloved #SanGabrielMission, founded in 1771, devastated by fire before dawn,” Gomez wrote. “St. Junipero Serra, pray for this land that you helped to found.”

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