Scores of law enforcement officers on Monday converged on the Islamic Center of San Diego, the region’s largest mosque, to confront reports of an active shooter at the complex, and police later said the threat had been “neutralized.”

No further official details about the circumstances of the incident or casualties were immediately available.

The San Diego-area branch of the Council on American-Islamic Relations said on its X account that at least one person was killed by a shooter at the mosque. The organization also said children were inside a school housed at the complex at the time of the incident.

The New York Times, citing an email message from the mosque’s chairman, Ahmed Shabaik, reported that at least one person, a security guard, had been killed.

At about the same time, the San Diego Police Department reported in a post on X that the “threat at the Islamic center has been neutralized.”

San Diego Mayor Todd Gloria first reported around noon PDT (1900 GMT) that he had been informed of an “active shooter situation” at the Islamic center in the Clairemont community of San Diego, California’s second-most populous city. The San Diego police posted separately that its officers were on the scene “for a reported active shooter.”

Footage from local television stations showed dozens of patrol cars on a highway bridge next to the Islamic Center, with police officers and their vehicles surrounding the grounds, aiming rifles at the facility.

Police in tactical gear armed with rifles also were seen perched on the roof of the mosque near its dome, and TV images from the scene showed armed officers on the ground making their way through the complex.

The Islamic Center in Clairemont is the largest mosque in San Diego County and houses the Bright Horizon Academy, a school providing Islamic education, according to its website.

“We strongly condemn this horrifying act of violence at the Islamic Center of San Diego,” CAIR-San Diego’s executive director, Tazheen Nizam, said in a statement.

“No one should ever fear for their safety while attending prayers or studying at an elementary school. We are working to learn more about this incident and we encourage everyone to keep this community in your prayers,” Nizam said.

California Governor Gavin Newsom was briefed on the “evolving situation,” according to his office of emergency services.

(Reporting by Mike Blake in San Diego; Writing and additional reporting by Steve Gorman in Los Angeles and Andrew Hay in Taos, New Mexico; Editing by Chizu Nomiyama and Rosalba O’Brien)