An off-duty officer with the California Highway Patrol was severely beaten by a mob of teens during an altercation at a shopping mall in a suburb of Oakland on the day after Thanksgiving.

According to Fox News, the officer—identified only as Greg B.—approached a group of teens as they confronted a woman who accused them of stealing her mobile phone.

The crowd of teens then turned their attention to the officer, surrounding him and unleashing a vicious attack, during which the officer sustained a concussion, a broken finger, and bruises.

The Emeryville (CA) Police Department said Monday that two juveniles, ages 14 and 16, were arrested while six others are still being sought.