The family of murdered Belfast man Robert McCartney have blamed republicans for a threat to burn them out of their homes and businesses.
Robert McCartney, 33, was killed near Belfast city centre
Police warned them of the threat saying "criminal elements" were behind it. Catherine McCartney blamed republicans.
Mr McCartney, 33, was stabbed in January. His family said IRA members were involved and witnesses are afraid.
Sinn Fein President Gerry Adams condemned the threat, but denied republicans were involved.
Mr McCartney, a father-of-two, was killed near Belfast city centre after a row in a bar. His family have blamed republicans for the killing and said witnesses are afraid to talk to the police.
"Whatever the family may or may not believe, or whatever the family may or may not say, no republican is involved in any threat against this family," Mr Adams said.
He said the family deserved justice and that the killers of Mr McCartney were "guided entirely by selfishness and self interest".
Mr Adams also criticised the police investigation of the killing, saying he "knows for a fact" that many of the people in the bar where the fight started had not been interviewed by police.
Catherine McCartney, one of Robert's sisters, said police told them of the threat on Thursday evening.
She said the family believed it had come from within the republican movement.
"For the past three months, we have been asking the republican movement to stop protecting the criminals who murdered Robert that night," she said.
Shaun Woodward said he backed the family's campaign
"And now today after our campaign, we get a threat saying our houses are going to be burned down.
"I'm not frightened for myself personally but I have four children here from 13-years-old down, so I have to take it seriously for them."
Ms McCartney said there was a threat to burn a sandwich shop owned by one of the sisters.
Police would not comment directly as the case involved the security of individuals.
However, Northern Ireland Security Minister Shaun Woodward said he had been fully briefed on the threats made to the
McCartneys and he took them "extremely seriously".
He said: "I have huge respect for the members of that family and what they
are trying to do and intimidation, wherever it happens is a very, very bad
He added: "I fully support the family in everything they are doing and I
fully support what the police are doing and I encourage anybody in Northern
Ireland to come forward and help."
A large majority of the European Parliament voted to fund a possible civil action by Mr McCartney's sisters if the current criminal inquiry failed.
The motion will now be considered by the European Commission, which has already pledged help, and EU ministers.
Any cash support would come from the EU's fund to help victims of terrorism.
This fund has never before been used to finance an individual legal case.