On Wednesday night, two plainclothes police officers dressed as protesters were exposed during a demonstration against police brutality in Oakland, California.

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The officer who had pushed back the protester took out his baton and began beating the demonstrator after the scuffle started. When a crowd began to surround the officers, the one using his baton drew his pistol and aimed it at the heads of those around him.
Photographs show that the people the policeman was aiming at were all reporters and photographers. Reuter’s photographer Noah Berger, freelance journalist Courtney Harrop, and San Francisco Chronicle photographer Michael Short were all threatened with the officer’s pistol, ostensibly for taking photographs of the scene.
The two officers soon arrested the man who had been beaten with the help of riot police who had been tailing and monitoring the protest march. The two plainclothes police have subsequently been identified as California Highway Patrol officers.
According to the DailyDot, protesters claim that the two undercover officers attempted to “disrupt the peaceful protest and provoke violence.” These witnesses say that the officers banged on windows and encouraged protesters to loot businesses.

These morons are one-trick-ponies - and not very skilled ponies at that. "Outside agitators"? You bet...