A man murdered in north Belfast on Tuesday was targeted in a "ruthless attack" as he sat in his car, police have said.
Danny McLean (54), a man who was described as known to police, was shot a number of times on the Cliftonville Road on Tuesday evening as he sat in a red Audi Q2.
Dissident republicans are among lines of inquiry being considered by detectives.
Detective Superintendent Jason Murphy described the attack as "brutal and ruthless".
“Danny didn’t deserve that, his family very clearly are shocked at Danny’s brutal murder and the public can help us, I hope, to try and piece together exactly what happened,” he said.
“Danny was killed after a number of shots were fired, it wasn’t a just single shot and it wasn’t a random shot, it was very clearly a deliberate attack on the vehicle in which Danny was sitting.
“Our thoughts are with Danny’s family, who are coming to terms with their loss.
“We will work tirelessly to seek justice for his murder to find the answers to his family’s many questions.”
Mr Murphy said the murder investigation is moving at a “significant pace”.
"We have deployed a significant number of our major investigation team officers to it today in recognition of the amount of work that needs to be conducted to secure the evidence that we think may exist within the local community and in the area of the Cliftonville Road and Clifton Gardens, " he said.
“Just before 8.15pm on Tuesday night, the victim who is Danny McLean parked the car in the area of the Cliftonville Road and shortly after parking the car, a lone gunman approached from the area of Clifton Gardens just across the road, fired a number of shots at Danny.
“Danny was killed at the scene and the gunman made off back towards Clifton Gardens.”
Mr Murphy said he believes the community can help officers with a number of key questions.
“I am seeking the public’s help in this appeal to come to us and talk to us about the things they may have seen, heard or know, and specifically I am looking for individuals who were in the area of the Cliftonville Road and Clifton Gardens on Tuesday night between about 7.30pm and 8.30pm to talk to us.
“I am keen to try and piece together the events of Tuesday in totality for Danny, to try to understand whether any of that gives us a clue as to how he was targeted and who he was targeted by.”
The murder was earlier condemned by Northern Ireland’s leaders.
First Minister Arlene Foster described the shooting as terrible news for people in the area and expressed her sympathies with the family of the man who died.
Ms O’Neill told the BBC: “At the heart of that is going to be a grieving family who lost a loved one last night and our thoughts are very much with the family.
“The police will have a job of work to do.
“This is not something that is acceptable at any level in our society and I think that anyone with information should come forward to the PSNI and assist with the investigation.” – PA