In a statement to local media, the Real IRA has claimed responsibility for the brutal murder of a man whose body was found dumped on a country road in a statement to local media.
Earlier, Martin McGuinness blamed the Real IRA for the murder.
Kieran Doherty, aged 31 and the father of a two-year-old girl, was stripped, tied up and shot in a remote lane outside Derry.
The detective investigating the killing said the murdered man, who was shot in the head, was soon to get married to his long-term partner.
Northern Ireland Deputy First Minister Martin McGuinness, who lives in Derry and revealed he knew the murdered man's family, blamed the dissident republican Real IRA for the killing.
‘I am outraged and disgusted at the murder of Kieran Doherty,’ said the senior Sinn Féin representative.
‘There is a widespread belief in Derry city that he was killed by the self-proclaimed Real IRA and I am calling on the 32 County Sovereignty Movement (aligned to the group) to give us an explanation why another young Derry man has been murdered.’
He added: ‘I think those people who were responsible for last night's dirty deed need to come forward and give an explanation to the citizens as to why they are continuing with these stupid and futile acts.’
Speaking at a press briefing in Derry this afternoon, Detective Chief Inspector Ian Harrison appealed for anyone with any information regarding the murder to come forward.
Chief Inspector Ian Harrison said Mr Doherty had met a savage and brutal death that was unjustified and unwarranted for any reason.
He said the PSNI had an open mind about the motives and that they would be liaising with gardaí as part of their inquiries.
A major forensic examination of the scene was being carried out today.
It is believed Mr Doherty left the family home at around 8pm last night to go to a local shop but there was no further contact until his body was discovered some two-and-a-half hours later at Braehead Road.
Asked about speculation that dissident republicans may have been involved, or the possibility that the killing may have been drugs-related, Chief Inspector Harrison said he was not prepared to comment and said he had an open mind about who was responsible.
Northern Ireland's political leaders have said incidents like last night's will not be allowed destabilise the peace process.
First Minister Peter Robinson said: 'I am sickened and disgusted at this murder, there is no place in our society for the people who committed this evil act.
'I remain determined as ever to condemn these acts to the history books and to help build a safe and peaceful society.'
