Four Washington prison inmates who were shipped out of state because of overcrowding are under investigation for allegedly assaulting prison workers in Oklahoma on Thursday.

The attacks took place at the North Fork Correctional Facility in Oklahoma, a private prison run by the Corrections Corporation of America. Washington has 304 of its inmates serving time in that prison, part of the 1,160 total number of inmates who are now out of state, said Washington prison official Gary Bohon.

A prison officer and sergeant were injured, treated at a hospital and released, said a CCA spokeswoman. The four offenders were placed in segregation.

Washington also has offenders housed in Arizona and Minnesota to prevent overcrowding in Washington’s 15 prisons, where the population is more than 17,000, including work-release centers.

Washington’s Department of Corrections plans to bring back a small number of offenders in the next six to eight weeks, Bohon said. And the state remains on track to bring back all of the out-of-state inmates by the end of 2009. That’s when a bigger prison at Coyote Ridge in Eastern Washington is expected to be fully operational. Bohon said the four inmates could be sent back to Washington or could face local charges as a result of the attacks.

Joseph Turner, The News Tribune