CHICAGO (CBS) – NATO protesters say they are being harassed and unlawfully arrested and even detained ahead of the summit.

The group Occupy Chicago says it is disgusted by the way some of their allies were treated. They say police busted their way through the doors to several apartments in a building near 32nd and Morgan.

The National Lawyers Guild says nine people were arrested as police sought out anti-NATO activists.

The group also says police showed residents a document they said was a search warrant but that the paperwork was never signed by a judge.

“In the United States we should be protected under the Constitution from unlawful search and seizure,” the Guild’s Kris Hermes said. “It’s not OK that police come in, break down a door without a warrant, arrest people and take them away and not indicate where they’re being held.”

Rachael Perrotta of Occupy Chicago says the detained individuals had traveled to Chicago to “stand up against the NATO war machine.”

Police Supt. Garry McCarthy said his department was making an “inquiry” into the claims.

Demonstrators took to the streets Thursday night on Chicago’s North Side, stalling traffic along the way, hours after the alleged morning police raid.

It wasn’t immediately known if the march was in response to Thursday’s purported arrests.