SPOKANE, Wash. -

Federal, state and local law enforcement agencies fanned across the region Thursday and executed search warrants on locations in Washington, Idaho, Nevada and California and arrested 29 people on federal drug charges for manufacturing and selling opiates.

A task force of FBI agents, Spokane Police and Spokane County Sheriff's deputies have been investigating the alleged drug ring for more than a year.

Law enforcement agents served search warrants throughout Spokane early Thursday, searching for evidence that people with ties to Spokane, California, Idaho and Nevada were selling ecstasy, oxycodone, methamphetamine and PCP.

The execution of the warrants and subsequent arrests were part of a year-long investigation that culminated with the raids in an attempt to disrupt a large-scale criminal enterprise.

More than 100 federal, state and local law enforcement agents searched 20 locations Thursday morning, with the lion's share of the arrests in the multi-state operation made in Spokane and Spokane Valley. Authorities said the criminal enterprise, while rooted in Spokane, extended as far south as San Diego, Long Beach and Las Vegas.

Officials say they expect to make more arrests in their ongoing investigation. Court documents say 39 people were indicted, and 26 of the people arrested had Spokane addresses.