Leading Ulster Volunteer Force paramilitary Mark Haddock is critical after being shot in County Antrim.
Part of the Doagh Road has been sealed off
The attack happened just before 1600 BST near Mossley Mill in the Doagh Road area of Newtownabbey.
It is understood Haddock, 36, has been taken to the Royal Victoria Hospital in Belfast with multiple wounds.
He is currently on bail on a charge of attempting to murder doorman Trevor Gowdy at a social club in Monkstown nearly four years ago.
Haddock was named in that court case as a leading UVF member. Judgement in the trial has been reserved.
It is understood Haddock was shot between five and eight times.
It is believed he then staggered out of the house and made his way to a neighbour's house and an ambulance was called.
Part of the Doagh Road has been sealed off as police carry out a follow up investigation.
Mark Haddock (circled) was shot near Mossley Mill
It is understood Mr Haddock had an address in the area for the last two-and-a-half years and had been living there on and off. He is originally from the Mount Vernon area of north Belfast.
BBC Northern Ireland home affairs correspondent Vincent Kearney said Mark Haddock was accused of several murders and membership of the UVF in the Irish Parliament last year.
"The claims were made by Pat Rabbitte, leader of the Irish Labour Party, in October," he said.
"Mr Rabbitte claimed Mark Haddock ordered the murder of Raymond McCord, 22, who was beaten to death by a UVF gang in Newtownabbey in November 1997.
"He also claimed Haddock had been involved in eight other murders - and said he had not been charged with any of them because he was working as a Special Branch informer who was allowed to act with impunity.
"Mark Haddock has not been charged in connection with any of the killings listed by Mr Rabbitte.
"However, the Police Ombudsman, Nuala O'Loan is conducting an investigation into the murder of Raymond McCord and that report is expected to be completed next month."
North Belfast DUP MP Nigel Dodds said he was shocked at the shooting.
"This is an appalling incident which will be condemned by all right thinking people," he said.
"Regardless of circumstances no one has the right to take the law into their own hands and I would call upon anyone with information to assist the police in order to bring those responsible to justice."
East Antrim assembly member Roy Beggs Jnr also condemned those behind the shooting.
"The perpetrators of this barbaric act must be swiftly taken off the streets and subjected to the fullest rigour of the law," he said.