(CNN) — The oldest Black church in California’s East Bay was devastated by a massive fire Sunday night that the church’s pastor said gutted its interior structure.

Video showed heavy smoke and flames shooting from the roof of the First African Methodist Episcopal Church of Oakland, where the fire erupted shortly before midnight, according to a tweet from the Oakland Fire Department. It quickly escalated to a three-alarm fire, the department said, with about 60 firefighters working to quell the blaze.

A fire investigator has been able to determine the “area of origin,” per the department, but the cause remains undetermined.

No injuries have been reported.

“We don’t know why, we don’t know who, but it’s burning down,” the pastor, the Rev. Rodney Smith, said in a video shared on the congregation’s Facebook page, adding the church’s interior structure had been lost and only the outer walls were still standing. “But I promise you this, we will rise again.”

The church is the first and oldest Black church in the East Bay, dating to 1858, according to the Oakland Library.

Per the Online Archive of California, it stood as the only African American church in Oakland for more than three decades. It was also the first school for people of color at a time when only White children could attend public schools — a history Smith highlighted in his video, shot at the scene of the fire.

“First AME Church Oakland was educating Black people 20 years before we were able to get public education,” he said. “The church feeds the community, serves the community in every way.”

“I’m completely devastated, completely at a loss for words,” he said.

The oldest Black church in California’s East Bay burns in three-alarm fire