SPOKANE -- A federal inmate stabbed a Spokane County Jail sergeant in the face while in the process of being transferred to another facility Wednesday morning.

Dan Jackson, KREM.com

Sheriff Ozzie Knezovich shows off a "flex-pen" similar to the one used by an inmate to attack a jail sergeant.

Sgt. Donald Hooper suffered two puncture wounds in his cheek and an ear laceration when he was punched by Michael J. Wigren, 26, about 7:30 a.m.

Wigren had tucked a fortified “flex pen” in his fist so that it protruded from between his fingers. The pen caused the injuries to Hooper’s face.

Hooper was taken to a downtown hospital where he was treated and released.

A Spokane City resident, Wigren was being held on federal charges for making threats to U.S. Senator Patty Murray and the FBI.

He reportedly was being transferred Wednesday to an East Coast federal prison to serve a one-year sentence.

When told by deputies early Wednesday that he was being picked up by deputy U.S. marshals for transport, he told staff he would require a private room where he was being taken.

Told there was no guarantee of that, the inmate became agitated.

Several additional deputies were called to the floor to help move Wigren out of his cell. However, he had soaped the window in the door of his cell and covered the food slot with a blanket.

When deputies pulled the blanket out so they could see him, Wigren replaced it with the mattress off his cot.

Sgt. Hooper ordered the inmate to back away and opened the door to remove the mattress.

Wigren immediately rushed from the cell with his fists raised and began punching the sergeant in the face, injuring him.

Deputies quickly swarmed the inmate and restrained him.

He was turned over to marshals and transported out of the Spokane County Jail as scheduled.