One of shooters in deadly attack at San Diego mosque was previously flagged by FBI

Officials seized guns from Caleb Vazquez's father last year amid alarm over teen's views on mass shooters and Nazism

One of the two white supremacist shooters who attacked a mosque in California on Monday and killed three people had already been on law enforcement officials' radar, according to US media reports.

Local officials were so alarmed by Caleb Vazquez's idolization of mass shooters and Nazism that they seized his father's guns a year before the shooting, the New York Times reports. Similarly, Bloomberg reports that Vazquez had already been flagged by the FBI as a potential threat" last year.