Hawai'i inmates scuffled at an Arizona prison yesterday when cell doors inadvertently opened, at least the fifth door malfunction at prisons run by the same private company.

Yesterday's incident was at Saguaro Correctional Center in Eloy, Ariz. Four previous incidents in which cell doors accidentally opened took place at Red Rock Correctional Center, another Eloy prison with Hawai'i inmates. Both are operated by Nashville-based Corrections Corporation of America.

"I am deeply disturbed by this incident," Clayton Frank, interim director of the Hawai'i Department of Public Safety, said in a written statement.

"We're demanding a thorough investigation and a complete review of CCA's correctional officers training program, as well as their computerized security system," Frank said.

The department reported last night that at about 2:30 p.m. Arizona time yesterday, 12 doors inside an administrative segregation unit were inadvertently opened at Saguaro Correctional Center.

Seven inmates came out of their cells, including two who got into a physical altercation. One of the two inmates suffered superficial injuries, the department said.

A third inmate refused several orders to return to his cell and was sprayed by a chemical agent, similar to pepper spray. The inmate then returned to his cell.

Corrections Corporation of America notified Hawai'i officials of yesterday's incident almost immediately, said a statement by the Department of Public Safety.

Medical personnel treated the three inmates, who then returned to their housing unit.

Human error caused the doors to inadvertently open, CCA officials told the state.

Hawai'i Deputy Director of Corrections Tommy Johnson and other senior corrections administrators are scheduled to go to Arizona this month for a full inspection.

The $95 million, 1,896-bed medium-security prison opened in June. Only prisoners from Hawai'i are housed at the facility.

In the most serious of the incidents at Red Rock Correctional Center, Hawai'i inmate John Kupa was stabbed with a homemade knife on June 26 after more than half of the cell doors abruptly opened in his housing unit. That incident was blamed on an error by a corrections officer.

Kupa, 36, was stabbed in the lower left back. He was treated at an Arizona hospital.

The man who stabbed Kupa, Hawai'i convict Sidney Tafokitau, said he acted in self-defense after being attacked.