Up to three men were involved in the Co Louth shooting of a father of one with republican links, gardai have said.
Sinn Fein led calls for anyone with information on the murder of Seamus McMahon to come forward after he was gunned down in a friend's house in Dundalk.
It is believed two men burst into the house on Sunday night and opened fire on the 41-year-old as a third man waited in a getaway car.
Local Sinn Fein TD Arthur Morgan strongly condemned the murder.
"The community in Saltown and the wider Dundalk area are in shock at last night's events. I strongly condemn this murder. The perpetrators of this crime must be brought to justice," he said.
"Anyone with any information should bring it to the gardai immediately."
It is understood Mr McMahon, who had a teenage son, was shot in the body and taken to Our Lady of Lourdes Hospital in Drogheda where he died from his injuries.
Detectives issued details of a car they believe may have been used in the attack - a white hatchback car, possibly a Toyota Corolla or Nissan Almera, seen near the Bothar Crinn area at the time of the shooting around 7pm.
Gardai said the two men who entered the house were tall and wearing dark-coloured hooded tops.
They first fled the scene of the attack on foot and left the house by jumping over a back wall into the garden of another house and running through to the front of other houses.
It is believed the pair jumped over a stone wall on the Bellewsbridge Road, where the white car was waiting, before making off towards the Fatima/Toberona Estate.
Gardai appealed for witnesses or anyone with information to come forward.
The area around the house was sealed off for a forensic examination and a post-mortem examination was also due to be carried out.
Local Green councillor Marianne Butler said the community was in shock after the attack, which took place in a new housing development on the outskirts of the border town.
"I can't remember the last time there was a shooting here," she said.
"My sympathies go out certainly to the families involved - it's a very tragic incident."
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