The man shot dead in west Belfast on Saturday was a well-known dissident republican, according to security, political and local sources. He was named locally on Saturday evening as Warren Crossan.
The murder attack happened at Rodney Parade, off the Lower Falls on Saturday afternoon.
The dead man had strong dissident republican connections. Just over six years ago his father, also a dissident republican, Tommy Crossan was murdered in a gun attack in west Belfast.
Tommy Crossan was involved in a split in the Continuity IRA where he was a senior Belfast commander.
Police were at the scene of Warren Crossan’s killing through Saturday. Detectives are trying to find a motive for the murder.
The two main lines of inquiry, it is understood, relate, firstly, to a feud within dissident republicans and, secondly, to the murder in Ardoyne in north Belfast in April of well-know Dublin criminal, Robbie Lawlor.
Lawlor was suspected of ordering the murder and dismembering of 17-year- old Keane Mulready-Woods in Drogheda earlier this year.
Warren Crossan had been questioned about the Lawlor murder.
The Sinn Féin MP for West Belfast Paul Maskey said local people were shocked by the murder.
“Those involved in this act have absolutely no place in our community, they must cease their anti-community activities and get off the back of the people of West Belfast,” he said.
“Those responsible must be held accountable before the courts,” he added.
Mr Maskey urged anyone with information to bring it to the PSNI. He said the killing was “brutal and shameful”.
Belfast SDLP councillor Brian Heading said those responsible for the "barbaric crime" had no local support. "They need to be caught and brought to justice. I would encourage anyone with information to bring it to the police as soon as possible," he said.
The West Belfast People Before Profit Assembly member Gerry Carroll said people were "outraged at this horrific attack".
“These kind of barbaric actions heap pain and trauma on our community. They have no role in our society. My thoughts are with this individual and their family,” he said.
Alliance MLA and Policing Board member John Blair said the “brutal attack” had left another family mourning.
“There is never any excuse for guns and murder on our streets and we all have a role in preventing that and stopping a recurrence of these tragic events,” he said.