Secretary for Security Ambrose Lee has expressed concern over a prisoner's attack on Stanley Prison staff members.

Speaking to the media this morning, Mr Lee said he has every confidence the Correctional Services Department has the experience and ability to handle this kind of violence.

He said he spoke with the department's Commissioner this morning and was told this was an isolated incident.

Mr Lee said the department will set up a team to see if the current security measures need improvement to prevent the recurrence of similar incidents.

The attack happened inside an interview room at Stanley Prison at 12.08pm yesterday when a prisoner was attending a Justice of the Peace interview.

The prisoner suddenly threw some powder at a Chief Officer and attempted to attack the Chief Superintendent with a piece of metal.

Other staff members immediately subdued the man, and three of them sustained minor injuries while restraining him.

During the attack, Chief Superintendent Cheng Man-wai sustained a superficial cut over his right temple and minor cuts to his right hand and right little finger while seizing the piece of metal.

The Chief Officer sustained a graze over his right eye.

Mr Cheng, the Chief Officer and two staff members went to Eastern Hospital for treatment.

Investigations by the Police and CSD are proceeding.