Cardinal Keith O'Brien is being investigated for sexually assaulting a priest only hours after he was ordained a cardinal.

According to, O'Brien allegedly made an attempt to grope a Scottish priest at the Scots College in Rome in October 2003. The priest, who is now based in London, made a formal complaint to the the Vatican's Congregation of Bishops last September, after which the newly-appointed cardinal was summoned immediately to Rome.

The complaint was the first which eventually led to the cleric's downfall. The  priest, who was known to Cardinal O'Brien, is not one of the four complainers whose allegations went public last month.

Allegations of sexual misconduct within the Vatican could be more detrimental to the former Archbishop of St Andrews and Edinburgh that any other claims he is facing, according to senior sources within the Catholic Church.  O'Brien, who becamea cardinal on October 21, 2003, under Pope John Paul II, could become only the fourth cardinal in 200 years to be stripped of his position.

"If Pope Francis wasn't familiar with the problems faced by the Church in Scotland, he certainly is now," said one source.

O'Brien has retreated into privacy following revelations that he "behaved inappropriately" towards three priests and a now former priest, who alleged he was abused by the CArdinal while at a seminary as a teenager in the 1980s.

Following these claims, the cardinal has been relieved of his post as Archbishop of St Andrews and Edinburgh and subsequently admitted his sexual conduct had "fallen below the standards expected of me as a priest, archbishop and cardinal."

Said a spokesman for the Catholic Church in Scotland: "A number of complaints have been passed directly to the Vatican.

"The detail and nature of them is not known to the Bishops' Conference of Scotland."

Cardinal Keith O'BrienGoogle Images