A former Roman Catholic priest has been found guilty of sexually abusing boys at the London school where he taught in the 1970s and 80s.

Fr Laurence Soper, 74, had previously fled to Kosovo after withdrawing £182,000 from a Vatican bank account, fleeing accusations of sex abuse against minors. He had been extradited back to the UK to face 19 charges of indecent and serious sexual assault against 10 pupils while headmaster at St Benedict's School, Ealing.

Yesterday an Old Bailey jury found him guilty on all charges, according to BBC News.

Prosecutor Gillian Etherton QC had told the London court: 'It is the prosecution's case that 'punishments' as described by the complainants in this case were carried out by Soper in entirely inappropriate ways and circumstances and on many occasions with what can only have been sexual motive.'

She added that he had used 'fake reasons' to justify punishments; students could face a caning – or sexual assault – for 'failing to use double margins', and 'using the (wrong) staircase'. It was heard that Soper, described by an alleged victim as a 'sadist', offered more lenient beatings with the cane if students would receive it with their trousers off.

Soper, formerly the Abbot of Ealing, has denied all the charges laid against him. 

He was living in Rome at the headquarters of his Benedictine order when was called to the UK to be interviewed about the claims of abuse. He was granted bail to return to Rome, but fled to Kosovo in March 2011 just before he was due to attend a police station in the UK, taking 204,000 euros with him. He told the court he fled the country out of 'stupidity and cowardice'.

The judgment follows four other allegations of sexual abuse at the hands of teachers at the private school. The most recent conviction was that of the 'devil in a dog collar' Father David Pearce, who was jailed in 2009 after admitting to 11 historic charges of indecent assault. In a statement heard by the court St Benedict's apologised for 'serious wrongs of the past'.

'The school regrets that Soper did not have the courage to plead guilty,' said Lord Carlile QC.

'The result has been that innocent victims, whom he abused when they were boys in the school, were compelled to give evidence. The tough lessons of the past have been learned, and the errors and crimes of the past are in the daily consciousness and conscience of the school management.'

Soper is being held in custody and will be sentenced on December 19.