A convicted rapist has been jailed for four years after admitting a sex attack on a woman more than 21 years ago.

Phil Collins, who is already in prison for two other rapes, was sentenced at Basildon Crown Court today after pleading guilty to indecent assault on a 19-year-old woman on May 27, 1991, Essex Police said.

The attack happened in South Ockendon, Essex.

Collins, 53, previously known at Philip Treble, was jailed for 10 years in 2010 after being found guilty of what a judge described as a "terrifying attack upon a 17-year-old girl" in Gippeswyk Park, Ipswich, in January 1990.

The following year he was given a second, 13 and a half year sentence to run alongside the earlier term, after admitting the rape and indecent assault of a woman in her Ipswich home in 1987.

Referring to his latest conviction, Detective Inspector Jo Williams, from Essex Police, said: "The victim is extremely relieved that at last the man who attacked her has been identified and has today admitted his guilt.

"She is grateful that her case was never closed and is thankful that she will not have to give evidence and can finally get on with her life."

Collins was arrested in prison in October last year by Essex Police's cold case investigation team.