A Catholic church has been "desecrated" for a second time after a man lit fires and left satanic images at the altar, the diocese said.
The incident at St Mary's church, Great Yarmouth, Norfolk, was caught on CCTV.
The church said footage showed a man lighting small fires before attempting to burn a sacred icon he took off the altar and put a picture of a satanic figure in its place.
Norfolk Police said it was treating it as a religiously aggravated hate crime.
Parish priest Fr Anthony Nwankwo said something similar to Tuesday's attack happened four months ago when someone came into the church and left a satanic picture at the foot of a cross at the back of the church.
He added: "Our church and sanctuary has been desecrated. We will not close the church but to use the altar and sanctuary we need to go through a service to re-consecrate the area."
Parishioner of 33 years Brian Lafferty said he was appalled.
"I have never seen anything like it before and it is quite disturbing really, especially in this day and age."
The Roman Catholic Diocese of East Anglia said it intended to keep its churches open despite the religious attack.
"I am very saddened by what has happened, especially in Holy Week," Bishop of East Anglia Alan Hopes said.
"I am hoping it is not a hate crime, but whoever did it needs to know that he is already forgiven because that is part of who we are as Christians."
Investigating officer PC Lewis Gilmore said the CCTV was being examined and the force was appealing for further information.
"We are treating this very seriously and this is being investigated as a hate incident," a police spokesman said.