23-year-old Berkeley native Hersh Goldberg-Polin was at the Saturday music festival near the Gaza Strip that was invaded by Hamas militants, and he is believed to have been taken hostage.

It’s being reported that at least 11 Americans were killed in this weekend’s Hamas attack on Israel, with an unknown number of Americans among those taken hostage by Hamas. And on Saturday, the Jewish News of Northern California reported that 23-year-old Berkeley native Hersh Goldberg-Polin is believed to be among those hostages. According to that publication, Goldberg-Polin attended the music festival attacked by Hamas, and his parents heard from him Saturday morning in WhatsApp messages saying “I love you,” and “I’m sorry.”

Tuesday morning, Goldberg-Polin's parents confirmed more details about his disappearance at a press conference. Goldberg-Polin, who was born in Berkeley and moved to Israel at age 7, sent more detailed messages to his parents amidst the chaos of the attack. According to his father Jon Polin, the young man and his friends fled to a bomb shelter when "masked gunmen attacked," and Goldberg-Polin reportedly lost an arm trying to fend off the attack.

"As grenades were being thrown in, they were tossing them back out," the father Polin said, basing his account on what he’s heard thus far from other eyewitnesses.

His mother Rachel Goldberg added, "We know his arm was severed from the elbow-down, blown off." Accounts they have heard indicate Goldberg-Polin used a shirt to fashion a tourniquet to tie around his arm.

His last-known whereabouts were at the Israel-Gaza border, according to cell phone signals. Again citing eyewitness accounts, Goldberg said her son was "put on a pickup truck and driven away by Hamas."

The tragedy has also touched Berkeley with one of those American deaths. KTVU also reports that the nephew of Rabbi Yonatan Cohen of Congregation Beth Israel, Yoav Malayev, was also killed in Saturday’s attacks. Malayev was a member of the Israel Defense Forces. He was 19.

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Image: SV Werder Bremen via Twitter