Lawsuit claims FBI warned mother of suspect before San Diego mosque shooting

The FBI warned the parents of one of the teenage suspects about his concerning comments regarding school shootings on the dark web just days before a shooting at a California mosque left three people dead, according to a lawsuit filed by his mother.

According to the Associated Press, federal authorities contacted the mother of Caleb Vazquez on May 14, warning her that her 18-year-old son had been making troubling remarks about school shootings online. Vazquez's mother allegedly passed the warning to staff at the mental health treatment facility where he was staying and receiving care.

The FBI warning came days before Vazquez and another teenager, 17-year-old Cain Clark, allegedly carried out the shooting at the Islamic Center of San Diego. Three people, including a security guard, were killed in the attack before the two suspected gunmen were found dead inside a vehicle from what police said appeared to be self-inflicted gunshot wounds.

Police had rushed to the mosque after receiving reports of an active shooter. San Diego Police Chief Scott Wahl said officers arrived within four minutes and found three victims dead outside the Islamic Center. Authorities also received reports of gunfire nearby, including an incident in which a landscaper at the site was fired upon but not hit. Dozens of police vehicles surrounded the Islamic Center as officers launched an active-shooter response and searched the mosque and an adjacent school. Authorities briefly placed the area under lockdown and urged residents to remain indoors before declaring the threat neutralised.

The suspected shooters were later found dead in a vehicle in the middle of a nearby street. Wahl said they appeared to have died from self-inflicted gunshot wounds and that no police officers had fired their weapons.

The lawsuit filed by Vazquez's mother alleges that Park Mental Health Treatment of San Diego failed to intervene despite warnings about her son's behaviour. Vazquez was receiving treatment there for mental health problems, including depression and psychotic episodes, according to the court filing. The lawsuit says Vazquez had previously been hospitalised after telling a classmate that he wanted to carry out a school shooting. Authorities had also flagged his behaviour a year earlier and confiscated 26 guns belonging to his father under California's red-flag law.

Authorities have said Vazquez met Clark online and that the two were radicalised there. Police have not disclosed further details about their relationship or said whose weapons were used in the shooting. The mental health facility has disputed the allegations, saying neither Park nor its employees were responsible for Vazquez's actions.