Mikhail Gallatinov and Marc Goodwin tie the knot in first same-sex marriage to have taken place in a prison since equal marriage act was introduced last year

Two convicted murderers detained in one of Britain’s toughest prisons have become the first gay couple to marry behind bars.

Mikhail Gallatinov, 40, and Marc Goodwin, 31, held a modest service in the top security jail’s visitor centre, the Mirror reported.

It is believed to be the first same-sex marriage or civil partnership to have taken place in a prison since the equal marriage act was introduced last year.

Gallatinov is a convicted paedophile who was sentenced in 1997 for murdering a man he had met through a gay chat line. At his trial, Judge Rhys Davies QC said it had been a “cold-blooded, well-planned, callous, chilling and apparently motiveless killing”.

Goodwin was jailed 10 years later for a homophobic killing on Blackpool seafront that was described by police as “a savage, senseless homophobic attack that resulted in the death of a harmless man”.

Both men are serving life sentences at Full Sutton prison in East Yorkshire.

At their wedding ceremony, the pair exchanged personal vows they had written in front of a congregation which included relatives, a few fellow prisoners and four prison officers who had also been invited.

A source who visits Full Sutton regularly previously told the Guardian that the relationship had been well known inside the jail. “These two guys were on separate wings at Full Sutton and used to meet – and have sex – in the prison library. Then they managed to get on the same wing and had sex regularly,” she said.

A Prison Service spokesman confirmed the wedding had come at no cost to the taxpayer. “We are very clear that if prisoners do get married, the taxpayer does not foot the bill for the ceremony and they are certainly not allowed to share a cell,” he said.

Under the terms of the Marriage Act 1983, all prisoners can exercise their right to marry under civil law in the place of their detention. Gay inmates are now legally allowed to marry in jail following the introduction of the Civil Partnerships Act 2004 and the Marriage (Same Sex Couples) Act last year.