PLEASANTON, Calif. (KGO) -- An event that trains law enforcement turned into a platform for police protest.
Protesters with signs and fists in the air, called for the Urban Shield Police Law Enforcement Expo to stop.
Some even risked jail to prove their point by doing things like chaining themselves together to block one of the gates.
"They are fundamentally violent and oppressive, we believe true safety means building our communities," said Protester Mohamed Shehk with Critical Resistance Organization about police.
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It'a an expo that gives officers a first hand look at new high tech tools to improve their police work. The event was moved to Santa Rita Jail.
A group took their rally to the Alameda County Jail where they waited for the release of 20 others arrested.
"It's hard for me to understand, why you wouldn't want police and fire paramedics to be properly trained for critical sites, like an earthquake, a disaster, like a terrorist attack," said Sheriff Gregory Ahern with the Alameda County Sheriff's Department.
While the majority of the crowd passionately expressed their displeasure with police, one lone Pleasanton resident didn't support the protesters.
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"They're training is intense, their presence is intense, but what's happening in our country? We need that right now," said Caroline Page with the Pleasanton resident.
"They train to learn better tactics, share technology and weaponry in order to learn how to better oppress, control and harm our communities," said Shehk.
Urban Shield is now in it's tenth year.
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Demonstrators protest Urban Shield police training in East Bay