By Harriet McLeod

CHARLESTON, South Carolina (Reuters) - A corrections officer taken hostage at a maximum security prison in South Carolina by inmates who dressed him in an inmate's uniform was rescued early on Wednesday morning.

The rescue occurred about 4:30 a.m. local time and involved about 100 officers. It followed hours of negotiations with inmates, who had demanded such things as pizza and magazines, according to Clark Newsom, spokesman for the state Department of Corrections.

"He was bloody on the head, but he walked out," Newsom said.

The officer, whom officials would not identify, had been helping a nurse dispense medication in a patient unit of Lee Correctional Institution in Bishopville on Tuesday night when he was jumped by several inmates, Newsom said. The nurse escaped.

Prison officials learned of the incident when other inmates with illegal cell phones called a county police dispatcher, according to Newsom.

Initial efforts to rescue the guard, that included tear gas and an attempt to blow open two secure doors, were unsuccessful, Newsom said. Police eventually accessed the wing through other secure doors.

Newsom said the incident is being investigated to determine which inmates were involved and who will face additional charges.

In 2008, a prison employee at the prison was held hostage by an inmate without being harmed.

(Editing By Colleen Jenkins and Bob Burgdorfer)