By Betty Yu

OAKLAND (CBS SF) — Several protesters were arrested and two police officers injured Saturday night in violent confrontations with a splinter group of about 70 demonstrators who marched through downtown Oakland streets following an day of peaceful May Day protests.

Fearing a repeat of the widespread vandalism and damage done during a protest last month, Oakland police officers were out in force, shadowing demonstrators to make sure they remained peaceful. The department had canceled days off for all its officers.

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On Saturday evening a group of approximately 70 demonstrators — staging an “Abolish the Police” demonstration — marched from Frank H. Ogawa Plaza to the surrounding streets and downtown area.

“Individuals in the group began assaulting officers by throwing bottles and cans, two OPD officers sustained injuries,” OPD PIO Officer Johnna Watson said in an email.

Officers arrested at least seven people in connection to the assaults at 10th and Castro Streets.

“Officers arrested those individuals committing various crimes such as assault on an officer, assault with a deadly weapon on an officer and resisting/delaying/obstructing an officer,” Watson said.

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Local businesses owners said they have been preparing for the event in their own way. Some closed up shop early.

“My thing is like you protesting – fight for it – but peacefully, with your mouth, not with your hands, with you know breaking things. That’s not going to resolve anything, that’s just making more problems instead of resolving the situation,” said business owner Estrellita Garfias.

She added reinforcements to her glass windows at her automotive business.

“No issues over the last year with the protests. We’ve been one of the only businesses on the block to remain unscathed, no graffiti, no broken windows so all we can do is hope for the best, prepare for the worst…” said Quane Woods, General Manager of Gus’s Fried Chicken.

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Watson said the protesters all left the area around 10:30 p.m. and the downtown area was quiet overnight.