Police in Downpatrick have begun a murder inquiry after a man was found dead in a house in the Co Down town.
The PSNI said a man in his 30s had been arrested.
"Detectives from our Major Investigation Team have launched a murder investigation following the death of man in Downpatrick," a spokesperson said.
"A man aged in his 30s has been arrested."
Police are at a scene at Marian Park in the town.
The ambulance service said it had been called there around midday.
Priest asked to hear Confession
It comes as police investigate the serious assault of a priest in a church in Downpatrick this morning.
Canon John Murray was hit on the head with a bottle as he prepared to say 10.30am Mass in St Patrick's Church.
He sustained a serious head injury and is receiving treatment in hospital.
He had been asked to hear Confession by the man who went on to attack him.
The church has confirmed that Canon Murray, who is in his 70s is seriously ill, but stable in hospital. The church has asked for parishioners to pray for him.
This evening scores of parishioners gathered at St Brigid's Church to pray for the family of the man who was murdered and for the recovery of Canon Murray.
They said they were horrified by what had happened in their town, to the deceased man and to their parish priest who was on the cusp of retirement.
Celebrant Fr Martin Graham said he had come to stand with the people who have been so devastated by the events of the previous 24 hours.
He said it was "poignant" that Canon Murray was supposed to have said his last Mass this morning and described what had happened as "grotesque".
SDLP's Colin McGrath said the community is 'in shock'
"It's very concerning and disturbing that this attack occurred towards a priest who was vulnerable in the course of his ministry and service to the local community," said Fr Eddie McGee, spokesman for the Diocese of Down and Connor.
"Obviously, our thoughts and prayers are with Canon John Murray.
"Canon Murray was due to retire as parish priest in the coming weeks and will continue to serve in the local family of parishes."
Newry, Mourne and Down, District Commander Superintendent Norman Haslett said: "Police attended an address in the Marian Park area following a report of a deceased man at approximately 12pm on Sunday afternoon, 10 August.
"A 30-year-old man has been arrested on suspicion of murder, and remains in police custody assisting with enquiries.
"Enquiries are at an early stage and, at this time, we suspect this may be connected to a serious assault in the St Patrick's Avenue area of Downpatrick on Sunday.
"I am appealing to anyone who believes they may have information which could assist us with our investigation to contact us."
'Deeply shocking' incidents, says local MP
Sinn Féin MP Chris Hazzard has expressed his shock following the death of a man and an attack on Canon Murray.
"What has happened in Downpatrick is deeply shocking," the South Down MP said.
"The death of a man, along with the vicious attack on Canon Murray in St Patrick's Church, has deeply saddened and horrified the local community."
SDLP Downpatrick Councillor Conor Galbraith visited the scene at Marian Park.
"This is a very difficult day for people in Downpatrick after these two incidents and I have visited the Marian Park area to show my support to those affected," he said.
"This is an ongoing situation and I would ask people to give police time and space to carry out their investigations."
"People locally are devastated that this has happened on their doorsteps," he added.
Parishioners gather to pray for attack victims
Scores of parishioners are gathering at St Brigid's Church in Downpatrick to pray for the family of the man who was murdered and for the recovery of Canon Murray.
They said they were horrified by what had happened in their town, to the deceased man and to their parish priest who was on the cusp of retirement.
Celebrant Fr Martin Graham said he'd come to stand with the people who's been so devastated by the events of the previous 24 hours.
He said it was "poignant" that Canon Murray was supposed to have said his last Mass this morning and described as "grotesque" what had happened.
