Topeka ? Kansas prison officials have removed all inmates housed at a county jail after four inmates escaped, including a convicted murder who remains at large.

Department of Corrections spokesman Jeremy Barclay said Thursday that the remaining 18 prison inmates who were being held in the Ottawa County Jail because of prison overcrowding have been returned to the state prison in Ellsworth.

Barclay says the temporary decision was made after four inmates escaped Wednesday morning from the jail in Minneapolis, a small town about 120 miles west of Topeka.

Two of those men, including a convicted killer, were still missing Thursday.

Barclay says the move is temporary as the department investigates the escape and reassesses placing inmates in the jail.

Kansas allows some county jails to house prison inmates under state contracts to help alleviate prison overcrowding.