San Diego Mosque Shooting Highlights Copycat Extremist Violence Trend

Three men were fatally shot Monday at a mosque in San Diego in what experts describe as the latest case of hate-motivated shooters emulating prior attackers, aiming to provoke racial conflict and societal collapse.

The two shooters, aged 17 and 18, killed Amin Abdullah, 51, a security guard at the Islamic Center of San Diego; Mansour Kaziha, 78, a mosque elder and founding member; and Nadir Awad, 57, a neighbor whose wife taught at the center’s school.

The suspects died from self-inflicted gunshot wounds after the attack.

Investigators say the pair were deeply immersed in online extremist networks and idolized shooters who killed dozens in U.S. places of worship, schools, and stores. In a 75-page manifesto left before the attack, they expressed hatred for Muslims, Jews, Black people, the LGBTQ+ community, women, and both U.S. political parties.

They also livestreamed the violence and wrote on their firearms with white markers—common tactics among online-radicalized shooters, said Matthew Kriner, executive director of the Institute for Countering Digital Extremism, which analyzed the suspects’ digital footprint.

“Preliminarily, we’re seeing two individuals who jointly radicalized into this digital space and then jointly radicalized into this moment of violence,” Kriner said.

Vice President JD Vance on Tuesday called the shooting “reprehensible” during a briefing.

“The principle of religious violence is particularly disgusting, especially in the United States of America,” Vance said. “And as a devout Christian, I would say it’s one of the most anti-Christian things and anti-American things that you could do.”

Following the killing of Charlie Kirk in Utah in September and assassination attempts on former President Donald Trump, Trump and his allies have blamed Democratic and left-wing rhetoric for fueling political and extremist violence.

Earlier this month, the White House released its counter-terrorism strategy, identifying “Narcoterrorists and Transnational Gangs, Legacy Islamist Terrorists and Violent Left-Wing Extremists, including Anarchists and Anti-Fascists” as the top domestic terror threats.

Experts note that a growing body of research shows recent high-profile U.S. shootings are mostly carried out by individuals heavily influenced by online spaces, where traditional political divides are largely irrelevant.

The counter-terrorism strategy did not mention white supremacist violence or online radicalization of youth, despite federal officials previously acknowledging those risks.

Over the past year, researchers and the FBI have warned of rising nihilistic violent extremism (NVE), defined by the government as violence “motivated by a hatred of society and a drive to cause its collapse through indiscriminate chaos.”

It remains unclear how many high-profile shootings are linked to NVE, but in February the FBI said it was investigating at least 350 people nationwide believed connected to NVE networks that coerce vulnerable young people into terrorism and sexual violence.

In March 2024, the FBI issued a notice warning against groups that radicalize youth toward hate-motivated violence using “threats, blackmail, and manipulation” to force them into harming themselves or the public.

And in March 2025, the U.S. attorney for the central district of Illinois announced that such groups continue to exploit digital platforms to radicalize children.

In their manifesto, the San Diego shooters repeatedly cited the man who killed 51 people at two mosques in Christchurch, New Zealand, in 2019. Kriner said this shows many violent extremists adopt the ideology of prior shooters rather than conventional political beliefs.

The 23-year-old who killed 32 people at Virginia Tech in 2007 was inspired by the Columbine High School shooters. Nearly a decade later, in 2016, authorities found a book about the Virginia Tech and Columbine shooters in the bedroom of an 18-year-old German who killed nine people at a Munich mall.

The 18-year-old who killed 10 Black people at a Buffalo grocery store in 2022 had been inspired by the Christchurch shooter, as well as shooters at an El Paso Walmart and a historically Black church in Charleston, South Carolina.

The gunman who killed two children at Annunciation Catholic School in Minneapolis in August 2024 expressed admiration for the 28-year-old who killed three children and three adults at a Nashville school two years earlier.

Kriner said most high-profile extremist shooters are not constrained by party labels like Democrat or Republican. Instead, their views combine fascist ideals with a belief that society is so degraded that extreme violence is necessary.

“The core belief of doing something, taking action, appeals across social racial, economic, and national lines,” Kriner said. “It makes it hard for us to find the motivating factor because everything becomes a factor.”