Post-mortem examinations will take place today on the bodies of the father and son found dead in Leterkenny on Thursday.
Investigations are continuing into the suspected murder-suicide.
The grim discovery of the bodies of a father and son were made by a neighbour in the Windyhall area of Letterkenny at around 2pm on Thursday.
The bodies of Daniel Duffy (88) and Damien Duffy (50) were found at the property.
Gardaí are not seeking anyone in connection with the deaths.
Both bodies have been removed from the scene to Letterkenny University Hospital where post-mortems are due to take place this morning by Sally Anne Collis, a State Pathologist.
"The results of the post-mortems will determine the course of the investigation," a Garda spokesperson said.
"The scene remains preserved at this time and the technical bureau continue to examine the scene."
The body of Daniel Duffy was found inside the house while the body of Damien Duffy was located in a car, which was parked in an adjacent shed, Gardaí have confirmed.
Garda sources say the incident is being treated as a murder-suicide. No firearm was used in the incident.
A Garda spokesperson added: "Gardaí in Letterkenny are appealing to any persons who may have any information in relation to the incident to contact them at Letterkenny Garda station on (074) 9167100, the Garda Confidential Line 1800 666 111 or any Garda station."
The Mayor of the Letterkenny-Milford Municipal District, Councillor Jimmy Kavanagh, said the people of Letterkenny were ‘very, very shocked’ by the tragedy.
“It is an awful tragedy and the sadness is heightened by the fact that we’re in the Christmas season,” Councillor Kavanagh said.
“Everyone is in shock at this news. It’s very hard to take in and come to terms with.”
The area was sealed off by Gardai after the alarm was raised.
Gardaí are trying to piece together a timeline of events. Mr Duffy senior had not been seen in the area in close-on a week.
The pair were big sports fans and both were former ESB employees.
Councillor Gerry McMonagle said: “It’s just very shocking. It is very tragic and it is all the more tragic with the time of year that we are in.”
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