Extensive arson damage to St Mary's Christian Brothers

The Fire Service attended the blaze on Saturday night

The principal of a school in west Belfast has condemned an arsonist who set fire to a school in west Belfast on Saturday.

CCTV footage captured the culprit using an accelerant to set fire to the oratory of St Mary's Christian Brothers School at about 2030 BST.

The principal, Jim Sheerin, said the cost of repairs would be £200,000.

The assembly hall was also damaged and exams due to take place on Monday have been disrupted.

Mr Sheerin said after seeing the CCTV pictures, he believed the lone arsonist was about 16-years-old.

He added, however, that while he did not know who was responsible nor their motivation for starting the fire, he was "absolutely certain" that a pupil at the school was not responsible.

"This is a person with a very poor value system, with no respect for our property, nor for the religious ethos which this building represents within the school," Mr Sheerin said.

"We have had minor incidents of vandalism before, but nothing on this scale at all."

About 175 pupils who were due to sit GCSE exams in the assembly hall have been moved to another part of the school.

Maintenance staff worked throughout Sunday to clean desks which will be used during the tests.

As well as the damage to the oratory, where school masses are held, a number of religious artefacts inside were destroyed.

Mr Sheerin said that these included crosses and crucifixes which dated back to the 1920s and had been used at the school's previous site at Barrack Street.

Other valuables destroyed included altar cloths and vestments brought back from the school's annual pilgrimage to Zambia.

Police have appealed for information about the attack.