A FORMER PRISON officer jailed for smuggling heroin and mobile phones into Mountjoy prison has been placed in protective custody at the Midlands prisons for his own safety. It is expected that he will serve his entire four-year sentence in isolation from other inmates because he would be at risk of attacks from other prisoners if he was among the general prison population.

Prison officers said they will not give Dillon O'Brien any "preferential treatment" and are disappointed that he has cast all prison officers in a negative light.

Prison officer O'Brien (37), who was in charge of landing B3 at Mountjoy prison, trafficked heroin and mobile phones to convicted murderer Thomas Hinchon, having received the items from Hinchon's brother Seán.

O'Brien received a four-year sentence on 7 December, and Hinchon was sentenced to three years concurrent with his life sentence. Judge Delahunt adjourned Seán Hinchon's case to March to allow a probation report on sentencing options to be prepared. She also ordered urine analysis.

O'Brien also brought vodka, mobile phones and cocaine to prisoner David Mulvey after being advised to do so by two men, and smuggled in mobile phones to another inmate Donnagh O'Brien.

O'Brien told gardaí he was addicted to cocaine, ecstasy and steroids, and he was getting two grammes of cocaine for every "drop". He brought the contraband into the prison in either his jacket or trousers pockets, and transferred the vodka to a bottle of water.

O'Brien told gardaí on arrest he was relieved the offences had come to light as he had been "leading a double life". The former prison officer is understood to have now recovered fully from his drug addiction.

"It is a very strange situation for him to be in; he went from being in charge of prisoners to becoming one of them," said a prison source. "Other officers are disgusted by what he has done; he gives all prison officers a bad name. He will not get any preferential treatment from prison officers. He will be treated exactly the same as any other prisoner."

Another inmate in protective custody at the Midlands prison is Stephen Egan, the mentally ill inmate who beat Gary Douche to death at Mountjoy prison in 2006 and was later found guilty of his manslaughter on the grounds of diminished responsibility.