YERBA BUENA ISLAND -- All lanes of the Bay Bridge have reopened about an hour and a half after protesters shut down all lanes just east of Treasure Island Monday afternoon, according to the California Highway Patrol, CBS Los Angeles reported.

A similar closure occurred in the Minneapolis area.

A group of demonstrators caused the shutdown of one direction of the San Francisco-Oakland Bay Bridge in a police-brutality protest tied to the Martin Luther King Jr. holiday.

Motorists exit their vehicles as protesters block traffic on the San Francisco-Oakland Bay Bridge on Monday, Jan. 18, 2016, in San Francisco. A group of protesters from the group Black Lives Matter caused the shutdown of one side of the bridge in a police-brutality protest tied to the Rev. Martin Luther King Jr. holiday. AP

Members of the group stopped vehicles in all the westbound lanes at about 4 p.m. Monday. They chained themselves and the cars together to form a line across the bridge and laid signs reading "BLACK HEALTH MATTERS" across the roadway.

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Traffic was blocked for travelers heading into San Francisco from the East Bay as the holiday weekend was ending.

About 30 minutes later, California Highway Patrol officers were pulling about a dozen protesters from cars and pulling their cars to the side of the road. Traffic soon began slowly moving again.

Mia Birdsong, a spokeswoman for the protesters, tells the San Francisco Chronicle they were from a group called Black.Seed, an offshoot of the Black Lives Matter movement.

Members of protest groups Black Seed and the Black Queer Liberation Collective took responsibility for the protest in a statement, citing recent police shootings, CBS LA reported.

"We are here to move towards an increase in the health and wellbeing (sic) of all Black people in Oakland & San Francisco," the groups wrote in a statement.

They were demanding divestment of city funds in policing, investment in affordable housing, the resignation of Oakland Mayor Libby Schaaf, the termination of San Francisco police Chief Greg Suhr and Oakland police Chief Sean Whent and the termination of police officers involved in several recent shootings.

Meantime, traffic resumed across a bridge linking Minneapolis and St. Paul after a Martin Luther King Day protest organized to highlight the deaths of two black men shot by police.

Nearly 100 people congregated on the bridge spanning the Mississippi River on Monday after marching from either St. Paul or Minneapolis. Police blocked off traffic on each side for 30 minutes while protesters chanted at its center.

Activists from St. Paul called for the case of Marcus Golden to be reopened. Golden was killed by St. Paul police last year, but a grand jury declined to indict the officers. Protesters from Minneapolis said they were worried the case of 24-year-old Jamar Clark will meet the same fate. They want video released of his shooting death by Minneapolis police last year.