The National Union of Journalists (NUJ) has reported the death threat against the Belfast-based journalist was made by loyalist paramilitary group, the Ulster Defence Association (UDA).
Seamus Dooley, the Irish secretary of the NUJ told the BBC the threat was credible.
“We understand this is a credible threat of violence, confirmed by the PSNI, and are therefore concerned for the safety of the journalist and those close to him,” he said.
Sinn Féin policing spokesman Gerry Kelly MLA said political unionism “has a responsibility to stand up to the paramilitary gang’s continued criminality” and called on the Democratic Unionist Party (DUP) to respond.
“The UDA threat against this journalist should be lifted immediately,” said Mr Kelly.
“This latest threat demonstrates once again the UDA’s contempt for democracy, the peace process, law and order and to those exposing their brutal criminality.
“This threat must be challenged head-on by all political leaders as there is no place in this society for the UDA or any other paramilitary group.
“There is an onus on political unionism and on the DUP in particular to show leadership by rejecting the continued existence of the UDA and ending its cosy electoral relationship with a gang still engaged in murder, extortion, drug dealing, and intimidation.”
East Belfast MP Gavin Robinson, the DUP’s spokesman on justice, home affairs, and human rights, called on anyone with information to go to the PSNI.
“Paramilitary activity and threats of this nature have absolutely no place in our society,” he said. “To seek to cause fear is something that should belong to Northern Ireland’s past. Society upholds freedom of the press. Nobody should feel intimidated as a result of the work they do.
“Anyone involved in illegal activity must face the full weight of the law. People with information must bring that forward to the PSNI.”
Amnesty International also condemned the threat.
“Such threats are not merely an attack on one journalist, they are an attack on the freedom of the press in Northern Ireland,” said Patrick Corrigan, Amnesty International’s Northern Ireland programme director.
“Guaranteeing freedom of expression must be a cornerstone of Northern Ireland as a peaceful and just society.”