PHOTOS: Protesters chain themselves to OPD, police union buildings

This image shows two women who chained themselves to the door of the Oakland Police Department on Thursday July 21, 2016. (Photo submitted to KGO-TV by Lyanne Melendez/Twitter)

Black Lives Matter protesters demonstrate outside police headquarters in Oakland, Calif. on Thursday, July 21, 2016. (KGO-TV)

This image shows a demonstrator who chained himself to the Police Officers' Association building in Oakland, Calif. on July 20, 2016. (KGO-TV)

This image shows protesters who chained themselves to the Police Officers' Association building in Oakland, Calif. on July 20, 2016. (KGO-TV)

This image shows a protester who chained herself to the outside of the Oakland Police Officers Association building on Wednesday, July 20, 2016. (Photo submitted to KGO-TV by Kristen Sze/Twitter)

This image shows protesters outside the Oakland Police Officers Association building on Wednesday, July 20, 2016. (Photo submitted to KGO-TV by Elissa Harrington/Twitter)

This image shows protesters who chained themselves to the Oakland Police Officers' Association on July 20, 2016. (KGO-TV)

This image shows protesters who chained themselves to the Oakland Police Officers' Association building in Oakland, Calif. on July 20, 2016. (KGO-TV)

This image shows protesters in Oakland chaining themselves to the Oakland Police Officers' Association in Oakland, Calif. on July 20, 2016. (KGO-TV)

OAKLAND, Calif. (KGO) -- Black Lives Matter protesters gathered outside the Oakland Police Officers' Association building on Wednesday, chaining themselves to the doors for a demonstration that lasted around 12 hours. The next day, they protested at Oakland City Hall and in front of police headquarters.

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