'Black Lives Matter' protests: Undercover police officer monitoring demonstrators points gun at Oakland crowd

A demonstration became heated when two undercover police officers had their covers blown

A plain clothes California Highway Patrol detective, who had been marching with anti-police demonstrators, aims his gun at protesters after some in the crowd identified him and his partner during an arrest in Oakland, California (REUTERS/Noah Berger )

Protesters at a demonstration in Oakland, California, were stunned when an undercover police officer pulled his gun on the crowd, after his disguise was blown.

A 150-strong group started the march at the University of California Berkeley’s campus on Wednesday - growing in size as it marched towards Oakland.

When demonstrators noticed that two fellow protesters dressed in plain clothes with bandannas over their faces were in fact police officers, they became agitated and began pointing and yelling: “Hey, they’re undercover cops!”

One Berkeley resident, who identified himself only as Dylan, told KTVU News that he pulled off the officer’s bandana.

The situation became heated when the officers began to walk away and the protesters continued screaming at the pair. One of the officers then pushed a protester aside.

The man responded by pushing back, before the officer tackled him to the ground and handcuffed him.

As shocked demonstrators gathered around, the second officer pulled out his gun and pointed it at the crowd. More officers quickly arrived, and the event came to an abrupt halt, and only a few dozen of the once 150 to 200-person-strong crowd remained.

Oakland police lieutenant Chris Bolton tweeted on Thursday that the officer was assigned to the California Highway Patrol, and was not an Oakland police officer.

Later, the patrol’s Golden Gate Division admitted to the the San Francisco Chronicle that officers had been dressing like and walking with protesters since the first demonstration on 24 November, attempting to gather intelligence to stop highway shutdowns.

Amid high tensions, Dylan told KTVU that he suspected that the officers targeted the man because he was black

“I'm a white man, and I pulled off (the officer's) mask, but they punched a black man,” Dylan said. “He got arrested.”

At one point during the march the group walked into a talk at Wheeler Hall, where PayPal co-founder Peter Thiel was speaking.

Demonstrators then forced their way into the auditorium, took over the stage and ended the discussion with chants of “black lives matter”, but were met with boos.

Since grand juries in New York and Missouri refused to indict police officers for shooting unarmed black men, protesters have flooded the streets of the San Francisco Bay area for weeks. Many protests have shut down highways, and some in Berkeley have turned violent, resulting in fires and looting.