The police have retained a presence in an east Belfast estate where some occupants have been forced out as part of the loyalist paramilitary feud.
Police have been observing the situation in Garnerville estate
A crowd of up to 100 UVF and UDA men gathered in the Garnerville area on Monday to prevent LVF members, who had been forced out, from moving back.
Removal men emptied one house in Glenlea Park. Police said they had not lost control of the estate.
The SDLP's Alex Attwood said Monday had been a "bad day" for policing.
"There was the appearance, not the reality, that in certain parts of this city, people who were in or who were associated with, or who may have been working on behalf of the paramilitary organisations, that their writ ran," he said.
"That's a very bad message, a very bad image and a very bad signal for policing. I think there's people in the police who know all that."
Mr Attwood, a member of the Policing Board, urged police to try to "frustrate" those trying to impose their will on the community.
A senior loyalist source told the BBC that UVF members went to the area on Sunday night and warned those with LVF links to leave.
A number of families left Glenlea Park at the weekend.
DUP East Belfast MP Peter Robinson said on Tuesday it was a "very worrying and very dangerous situation".
"Not just the issues relating to the Garnerville estate, but the potential is there for the whole situation to spiral and for other kinds of activities to be going on on other areas," he said.
He said police needed to be more pro-active against paramilitaries taking control of areas.
"There were activities going on in that estate which people were very unhappy about and the police weren't acting against that," he said.
"To some extent....communities start looking to paramilitaries to take the action the police are failing to take."
PSNI Chief Superintendent Wesley Wilson said there had disturbing scenes carried by the media, and admitted it had been a "difficult day" for policing.
However, he stressed that police had been pro-actively trying to deal with the feud.
"People may have got the impression that the police were not in control of that, but the police were in control. We would urge people not to take the law into their own hands."
He pointed out that families had already moved out of the area, when police arrived on Sunday evening.
Officers were monitoring and controlling the area, taking names of those wearing masks, and gathering evidence, he said.
"One of the difficulties for us was that there were no complaints from members of that community about those people being there," he said.
"We looked at what those people were doing in the area to see if we could gather any evidence of offences and if there had been any arrests to be made, we would have made them."
He urged politicians to mediate in the situation, but stressed that police needed information from the community.
"It really is something that politicians and others ... they need to get to grips with this.. and have some sort of mediation put in place to stop this feud," he said.
One resident said she welcomed what was happening in the estate.
"These fellas walked in and told everybody 'we are going to give you back your estate'.
"That's exactly what they've done - they've got a lot of support here for what they've done."
Two lives have been claimed in the dispute between the paramilitary Ulster Volunteer Force and Loyalist Volunteer Force groupings.