San Diego mosque shooters met online and left writings expressing hate, FBI says

SAN DIEGO (AP) — Two teenagers who shot and killed three people in an attack on a California mosque were radicalized online where they first met and shared white supremacist views, according to authorities and writings they authored.

The pair “didn’t discriminate on who they hated,” Mark Remily, the lead FBI agent in San Diego, said Tuesday.

The writings, obtained by The Associated Press, include hateful rhetoric toward Jewish people, Muslims and Islam, as well as the LGBTQ+ community, Black people, women, and both the political left and right. Both express beliefs that white people are being eliminated, and one writes about mental health struggles and being rejected by women.

Investigators also found at least 30 guns, ammunition and a crossbow at two residences after Monday’s attack in San Diego and were trying to uncover whether the shooters had broader plans, Remily said. The shooters, ages 17 and 18, killed themselves, police have said.

Authorities praised the three men they killed — including Amin Abdullah, a beloved security guard — for slowing the attackers at the Islamic Center of San Diego and preventing them from reaching 140 schoolchildren just steps away.

Imam Taha Hassane said Abdullah engaged the suspects in a gunbattle and called for a lockdown on his radio. He “sacrificed his life to stop them from getting inside the classrooms.”

The shooting was the latest in a string of attacks on houses of worship and comes amid rising threats and hate crimes targeting the Muslim and Jewish communities since the beginning of war in the Middle East, forcing increases in security.

Writings show shooters’ broad hatred

Authorities have not released the names of the suspects, but the writings are authored by Cain Clark and Caleb Vazquez. Soon after the shooting investigators were seen searching the San Diego home of Clark’s parents.

Authorities have said there was no specific threat against the Islamic center, which is the largest mosque in San Diego and also houses a school, police said. In Cain’s writings, he calls for Muslims to be “exterminated.”

The document includes symbols long associated with white supremacists and Nazis. The two referred to themselves as “Sons of Tarrant,” an apparent reference to the white supremacist who attacked mosques in Christchurch, New Zealand, in 2019, killing 51 people.

Muslim American organizations noted that anti-Muslim rhetoric has been on the rise across the U.S.

The two suspects met online before discovering they both lived in the San Diego area, the FBI said. “In terms of how the radicalization occurred, we’re still digging into that,” Remily said.

James Canning, a spokesman for San Diego Unified School District, said Clark had been attending school online since 2021 and was set to graduate next month. In 2024, he was a member of the wrestling team at Madison High School. Canning said Clark had no record of disciplinary issues in high school.

Neighbors Marne and Ted Celaya said they last saw Clark a few hours before the shooting and that he waved as he got into a car alone and drove away. They described the family as good neighbors and recalled watching Cain grow up.

“It’s unbelievable,” Marne Celaya said of the shooting. “He’s helped me bring in my groceries.”

The victims were pillars of the mosque

Police said the security guard opened fire when the shooters arrived at the Islamic Center and tried to barge inside.

As the shooters made their way into the lobby, they wounded the guard, who kept firing at them, forcing them back outside, where the attackers fatally shot him, Police Chief Scott Wahl said.

The pair went back inside and searched through rooms that were emptied during the lockdown, Wahl said. At some point, the two others who were killed drew the attackers farther away from the building, Wahl said.

Mosque leaders identified the victims as Abdullah, Mansour Kaziha and Nader Awad.

Kaziha, known as Abu Ezz, “was everything” to the Islamic Center, Hassane said. “He was the handyman. He was the cook. He was the caretaker,” Hassane said.

Abdullah had worked at the mosque for more than a decade.

“He wanted to defend the innocent so he decided to become a security guard,” said family friend Shaykh Uthman Ibn Farooq.

Mosque leaders were used to hate mail

The Islamic Center sits in a neighborhood with Middle Eastern restaurants and markets. It includes Al Rashid School, which offers courses in Arabic language, Islamic studies and the Quran for students ages 5 and up, its website says.

Josie-Ana Edenshaw, who has been going to the mosque for three years, said it was especially welcoming to new Muslims.

“They’ve always opened their doors, even to people who aren’t Muslim, they invite people to Ramadan dinners,” Edenshaw said. “Every person at that masjid will smile at you,” using the Arabic word for mosque.

The center’s imam said Tuesday that the mosque and its community wasn’t immune to threats over the years.

“We have never ever expected such things to happen at the Islamic Center of San Diego,” Hassane said. “I mean we are used to receiving hate mails, hate messages, people driving by and cursing and all that stuff. But such horrible crime, we have never expected this.”

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Biesecker reported from Washington and Seewer from Toledo. Eric Tucker in Washington; Mariam Fam in Winter Park, Florida; Jaimie Ding and Christopher Weber in Los Angeles; Hannah Schoenbaum in Salt Lake City; Javier Arciga and Gregory Bull in San Diego; and Gene Johnson and Hallie Golden in Seattle also contributed.

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