TACOMA, Wash. - Immigration protestors marched through downtown Tacoma, stopping traffic and halting downtown bus service Friday.

They're protesting federal immigration policy and the treatment of people at Tacoma's Northwest Detention Center, which holds as many as 1,000 people.

Protestors vowed to shut down the city of Tacoma Friday. They fell short but did get their message across. Many wore bandanas over their faces to hide their identities. The protest had been planned for weeks.

"When the ICE – Immigration Customs Enforcement - can come into our community, rip families apart, put people in jail. Whether or not they have papers, then something is wrong in our country," said Will Munger, protester.

Police arrested four of the protesters for obstruction of justice and assault on an officer. Three men and one woman were taken into custody.

The protest is permitted both Friday and Saturday, and has been successful in tying up traffic so far. The public bus service in the downtown core was temporarily suspended Friday, leaving many passengers stranded.