The Ulster Volunteer Force paramilitary grouping has been linked by loyalist sources to an attack in east Belfast.
Shots were fired through the front door
Shots were fired at a house in Sydenham and, according to one source, security measures at the house prevented the gunmen from getting inside.
The incident comes during a continuing feud between the UVF and the LVF.
Loyalists said the police have visited two bars on the Newtownards Road and on the Shankill to advise them of the possibility of an attack.
The shooting in Sydenham happened at a property on Victoria Road at about 2045 BST on Monday.
Four shots were fired at the house; two at the front window and two through the front door.
No-one was home at the time, but the owners believe the gunmen were looking for their 22-year-old son.
He does not live there, but he had visited the house that afternoon.
A short time after the attack, a car was found burning in a nearby underpass and police are investigating a possible link.
The DUP's Robin Newton, who described the attack as an "act of madness", said it may be linked to a loyalist feud.
"It could well be that someone walking along the street, a child, an elderly person, could have been caught up in the incident and we could have been looking at a fatality this morning," he said.
Police have appealed for anyone with information about the attack to contact them.