OAKLAND (CBS SF) — About 20 people were arrested during Sunday’s Battle of the Bay matchup between the Oakland Raiders and the San Francisco 49ers.

Alameda County Assistant Sheriff Case Nice told KPIX 5 that officers were still working on the paperwork as those arrested were being sent to Santa Rita jail, and that there could be 10 or 12 more arrests confirmed before the end of the night.

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Nice said there are usually about 10 arrests at an average Raider game.

One of the arrests was for possession of a firearm.

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“After the game, a fan reached into the trunk of his car and for some unknown reason put it in his waistband,” Nice said.

The Raiders upset the 49ers to win 24-13.

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