An 800-year-old 'Crusader' from a crypt in a Dublin church has been decapitated by vandals.
Archdeacon David Pierpoint told RTE the Crusader's head has been "severed from his body and taken away".
The discovery was made as a tour guide was preparing to open the church for visitors on Monday afternoon.
Archdeacon Pierpoint said he was upset and disappointed that the church has been targeted again by vandals.
The crypt of St Michan's was previously vandalised in 1996.
Archdeacon Pierpoint said the incident is devastating for the parish and community.
He said initially he was "quite disgusted" when he saw what had happened, but now he is "just sad".
"It's a sad day for the church and a sad day for humanity that someone would do such a thing."
Tours of the site are being cancelled for the foreseeable future. Last year around 27,000 people visited the church.
In a statement, the Church of Ireland said the crypt has been badly damaged and several of the mummies, including the 400-year-old remains of a nun, had been desecrated in the incident.
The Crusader's body was turned over and his head was removed.
Archdeacon Pierpoint said as a solid steel internal gate was also taken but the immediate concern is securing the vaults.
There are also concerns that the remains will disintegrate in the open air as the conditions in the crypt keep them preserved.
Gardai are examining CCTV footage.