Sydney prison officer charged over alleged inmate relationship after 'letters found'

A female prison guard has been freed on bail after being accused of engaging in a relationship with a maximum security inmate at Sydney's Parklea Correctional centre.

Ruby Burgess was arrested at a home in Bass Hill this morning and taken to Bankstown police station where she has been charged.

It comes after detectives began investigating an alleged inappropriate relationship between the 33-year-old correctional officer and a 37-year-old male inmate at the prison.

Police were handed the investigation after they say someone found a love letter written from one to the other, prompting them to review security vision.

It's alleged they found footage showing the pair walking into a storeroom together in area five of the jail, which is maximum security.

Detective Sargent Rob Hollows said managers of the facility reported the alleged relationship to police.

"We reviewed certain evidence and as a result of that we took swift and appropriate action," Det. Sgt Hollows said.

"It's quite concerning, and we take these matters very seriously because they do compromise the safety and good order of the facility."

The inmate is now being held in segregation and will be transferred to another prison.

Ruby Burgess was suspended from work a week ago pending the outcome of the investigation, and will face court later this month.