Police are investigating whether the murder of Bobby Moffett was sanctioned by the UVF leadership.
Speaking after a meeting of the Policing Board, Assistant Chief Constable Drew Harris said involvement of the UVF hierarchy was a possibility.
Mr Moffett (43), believed to be linked to the UVF, was shot dead by two masked men on the Shankill Road last Friday.
“There are a number of suspects that we would believe would be linked to the UVF,” Mr Harris said.
“So that is a very serious development and an active line of inquiry that we are pursuing.”
Mr Harris said the UVF remained a coherent organisation.
Mr Moffett's funeral is set to take place today. Tensions have been rising in the area since the murder and several people have said they have been threatened not to attend the funeral.
Yesterday it was revealed that the leader of the PUP, which is linked to the UVF, Dawn Purvis, had resigned following the murder of Mr Moffett.
Senior PUP members are to meet soon to decide on their future. But there is intense speculation that several leading figures in the party are to follow in the East Belfast Assembly Member's departing footsteps.
Some sources are suggesting they will form a new loyalist political group and attempt to distance themselves from PUP structures, while adopting many of the party's policies.
But there have also been reports that Ms Purvis, likely to remain an an independent MLA for East Belfast in the short-term, may consider joining the DUP or Ulster Unionists in the future.
UUP leader Sir Reg Empey initiated a Stormont tie-up with the party two years ago, which was blocked by Assembly rules.
In a party official statement yesterday, the PUP said they were losing “a great leader” and wished Ms Purvis well.
Interim leader John Kyle, who represents the PUP on Belfast City Council, said he was still committed to the political project of the PUP.
He added: “We need to take some time to take stock, review the situation and decide what is the best way to take forward the policies and projects we believe in.”
Mr Kyle said the broad daylight murder of Bobby Moffett last Friday had been “a major factor” in the decision of Ms Purvis — who took over from the late David Ervine in 2007 — to stand down
She said: “It's been very difficult but I know that I have made the right decision. I believe there are elements within the organisation, that have absolutely no interest in politics or the future of their party and no interest in the PUP.”
Ms Purvis said she was leaving with “a very heavy heart”.
“I believe the Progressive Unionist Party was founded by individuals who had a real vision for Northern Ireland and a positive and important contribution to make to politics and the peace process in this country. I have been honoured to be a part of that.
“However, I can no longer offer leadership to a political party which is expected to answer for the indefensible actions of others.”