Parklea prison guard stabbed by inmate

A prison guard has been stabbed twice by an inmate at a Sydney jail, reportedly escaping serious injury due to his name tag.

A 29-year-old inmate in the Parklea Correctional Centre allegedly attempted to strike the guard twice with a prison-made weapon on Wednesday afternoon, a spokeswoman for Corrective Services NSW told AAP on Thursday.

The first blow hit the guard's ID card while the second punctured his arm.

The prison's security team was forced to deploy gas and lock down common areas after the alleged offender incited other prisoners in the centre, who then refused to return to their cells.

NSW Ambulance confirmed to AAP that paramedics were called to the prison and transported a male patient to Blacktown Hospital.

The attack was slammed by the public sector union, which labelled it a failure by operators to run the centre safely and effectively.

"It's a miracle that this incident didn't result in more serious injury," it said.

Corrective Services NSW has launched a multi-team investigation into the privately run prison in July after a video was uploaded by an inmate in possession of a knife, a razor blade and the drug ice inside his cell.

The correctional centre, which houses maximum and minimum security prisoners, is privately operated by GEO Group Australia.

In the video, the male inmate describes the contraband items he has in his cell, claiming staff smuggle in mobile phones in exchange for money.

Four mobile phones, chargers, steroid tablets and other contraband was found after a major search of the prison was conducted. 

"Corrective Services NSW takes a zero-tolerance approach and uses a range of methods to track down and confiscate contraband… any suggestions that contraband is introduced by staff are immediately investigated," a statement said.