A 27-year-old man has been arrested in connection with a house fire in which three people died in Co Fermanagh.
He was arrested at the scene in Derrylin and taken to hospital for treatment, the PSNI said.
Detective Superintendent Jason Murphy said: "At this time we believe the fire, which has claimed at least three lives, was started deliberately.
"We are continuing to thoroughly examine the scene along with our colleagues in the Northern Ireland Fire and Rescue Service." RTÉ
reports that emergency services were called to, what the fire service described as, a "well-developed" blaze at a detached bungalow in Derrylin shortly after 7am.
Northern Ireland Fire and Rescue Service sent three fire appliances to the scene in the area of Doon Road and Molly Road.
The service tweeted: "We received a call at 7.14am this morning to a house fire in Doon Road, Derrylin, Co Fermanagh.
"Firefighters dealt with a well-developed fire in a detached bungalow. 3 Fire Appliances attended the incident. The fire is now extinguished and NIFRS remains at the scene."
The property had been rented out and the occupants are believed to have been living in it for around a year.
Police have appealed for anyone with information to contact them.
DUP leader and MLA for Fermanagh-South Tyrone Arlene Foster said on Twitter: "Horrific news coming from Derrylin, County Fermanagh, this morning. My thoughts and prayers are with the family and local community."
She said those who died were members of the same family.
"This is devastating news for the local community and there is widespread shock in the area."
Sinn Féin MP for the area Michelle Gildernew tweeted: "Devastating news for the family concerned and the Derrylin community. This is absolutely tragic, God help them all."
Speaking on RTÉ's News At One, the Fermanagh South Tyrone MP said: "This is an awful tragedy, not just for the family, but for the community here in Derrylin - where they lived, and for the neighbours and for the people who tried to respond to the fire this morning. Three people are dead. Our deepest sympathies go to the wider family."