Threats against Ulster Unionist Party (UUP) staff are being investigated by the police in Northern Ireland.
In a statement, the UUP said their "headquarters had received a number of calls of a threatening nature and we have alerted the Police Service of Northern Ireland to that fact."
It follows the party's refusal to form an electoral pact with the Democratic Unionist Party (DUP) in the North Belfast constituency.
The incoming UUP leader, Steve Aiken, had ruled out an election pact with the DUP in the forthcoming general election and said he would run a candidate in all 18 of the North's constituencies.
In an open letter published in the Belfast Telegraph on Thursday, 25 unionists from North Belfast – including current and former members of the UUP – outlined their “strong opposition” to any proposal to split the unionist vote in the constituency.
The current MP, the DUP's deputy leader Nigel Dodds, is defending a majority of less than 2,000, and they argue that any split could gift the seat to John Finucane of Sinn Féin.
Speaking on the BBC’s The View programme, Mr Aiken said his party had been “receiving threats to staff and members.”
This, he said, “undermines the entire principle of democracy, and it’s not the sort of thing we should be accepting.”
Mr Dodds said “any such incidents are deplorable and must be totally condemned.
“The only appropriate way to express your views and the most effective way to send a message in our society is through the ballot box,” he said.
