Church members on Sunday tackled a woman carrying a baby and handgun, as she threatened to blow up the church during Easter service, San Diego Police said.
The incident occurred as law enforcement and houses of worship were on heightened alert following deadly Easter Sunday bombings in churches and hotels in Sri Lanka.
San Diego Police arrived within two minutes of the first call and took the woman into custody, the department said in a statement.
The woman, identified by police as 31-year-old Anna Conkey, walked into the auditorium of Mt. Everest Academy around noon, San Diego Police Officer Dino Delimitros said.
Church Tsidkenu, a non-denominational church, leases Mt. Everest for church services.
Conkey walked onto the auditorium's stage and waved the handgun while she "made threats that she was going to blow up the church," police said.
"She was saying stuff that was kind of delusional. I was more worried about getting my family out of there," churchgoer Ronald Farmer said.
Churchgoers were able to take the baby from the woman's arms and pry the gun from her hands before tackling her to the ground, Delmitros said.
Church leader Ben Wisan told CNN affiliate KSWB that Conkey was familiar to the congregation.
"We know who she was," he said. "She had been coming on and off for a little bit of time."
A bomb-sniffing dog found nothing in a sweep of the building and the suspect's car, police said. Police said her gun was not loaded.
Authorities later found the woman's 5-year-old daughter "healthy and unhurt," police said. The two children are in protective custody.
Earlier Sunday, San Diego Police Chief David Nisleit announced that the department was stepping up patrols while it monitored the situation in Sri Lanka.
"At this time, there is nothing to indicate a connection to San Diego. However, in an abundance of caution, you will see extra patrols at houses of worship," Nisleit said on Twitter.
More than 200 people were killed in coordinated bombing attacks in Sri Lanka.
Though it's not clear who's behind the eight explosions that forced the country of 21 million people into lockdown, they are "certainly acts of terror," said Manisha Gunasekera, high commissioner of Sri Lanka to the UK.