Vandals broke into the crypt of a church in Dublin on Monday, damaging a number of remains before decapitating and stealing the head of an 800-year-old mummy of a crusader.
The Archbishop of Dublin, Diarmuid Martin, said he was "shocked" after hearing news of the incident at the Irish capital's St Michan’s Church.
"Not only have these individuals desecrated the sacred crypt but they have destroyed these historic mummies which have been preserved in St Michan’s for hundreds of years," he said in a statement.
"I would appeal to those responsible to examine their consciences and return the head of The Crusader to its rightful place."
According to the Church of Ireland, the 400-year-old remains of a nun were also "desecrated" in the incident.
“The actions of these people are devastating and sacrilegious," Archdeacon David Pierpoint, the vicar of the Christ Church Cathedral Group of Parishes, added.
"But also the crypt will have to close so tourists will not be able to visit. It is very frustrating."
This is not the first time the church has been targeted by vandals.
In 2016, thieves vandalised dozens of mummies in the search for valuable items, according to RTE.