The PSNI have warned the public not to approach Kieran McLaughlin, wanted in connection with the murder of Barry McCrory yesterday morning.
Members of the public are being "requested not to approach" Mr McLaughlin (58) under any circumstances by the Police Service of Northern Ireland (PSNI).
The PSNI took the unusual step in issuing the warning as it is believed Mr McLaughlin may have travelled south of the border as a murder investigation was launched into the death of Mr McCrory (35).
"Obviously we have an appeal out there, we're looking for information for where he is," a PSNI spokesperson said this morning.
When asked about the possibility of whether or not Mr McLaughlin had fled south of the border from Derry, the spokesperson said: "It's a possibility I'm sure. At this stage, we're asking the public for information on where he is.
"All I can say is that the public are requested not to approach this man," she added.
Mr McCrory was killed in Shipquay Street area of Derry yesterday morning.
He was fatally shot in his flat, and his partner was in the next room.
She was left injured but "distraught" at the death of Mr McCrory.
Mr McLaughlin has been described as being 5'7" tall, of medium build, with blue eyes and grey hair and is believed to be wearing dark coloured clothing.
Detective Chief Inspector Ian Harrison, who is leading the investigation, launched the appeal for information from the public after identifying Mr McLaughlin as a person of interest.
“First of all I want to make a direct appeal to anyone who was in the area of Shipquay Street this [Thursday] morning to come forward with any information that could assist with our enquiry," he said.
"We know that sometime between 10.30am and 10.45am a man carrying a rucksack entered a block of flats and shot and fatally wounded 35- year-old Barry McCrory. Barry’s partner was in another room of the flat at the time of the shooting.
"She was not physically injured but is understandably distraught by what has happened to her partner," he added.
Mr Harrison explained that the murder has been condmened within the local community and is appealing for any information from members of the public.
“We have already heard many within the local community openly condemn this murder and the people of this city are rightly outraged by what has happened here today," he said.
"That condemnation needs to be backed up with information. Barry’s killer needs to be found and dealt with by the courts and his family deserve answers.”
Anyone with information about this murder is asked to contact detectives at Strand Road on 0845 600 8000.
By Caitlin McBride