They were responding after the warning was daubed on a wall in the harbour area of the town.
A police spokesperson confirmed they were aware of a graffiti incident in the vicinity of Larne Harbour on January 21 and “this matter is currently under investigation”.
DUP MLA Gordon Lyons, who is also a junior minister at Stormont, said: “This must be condemned in the strongest possible terms. There is no place for this type of threatening language that harks back to days when other public officials and members of the security forces were targeted.”
Mr Lyons added that he understood unionist frustrations over the Northern Ireland Protocol and Irish Sea border but stressed there was no place for this type of threatening activity.
“Like many, I recognise the hugely detrimental impact that the protocol will have on Northern Ireland, its businesses, on jobs and consumers. However, there is simply no excuse for responding in this way and targeting people because they are doing their job.”
Alliance Councillor Danny Donnelly, who visited the location, said: “That is very disturbing. No matter your opinion on the Irish Sea border, threats to workers must be condemned by all.”
There was a similar rebuke for those responsible for the graffiti from Ulster Unionist MLA Roy Beggs.
Mr Beggs said: “I can understand the injustice felt by the entire unionist community following the introduction of a border down the Irish Sea, but I condemn the threats to staff carrying out their job. Such threats are likely to add to delays and difficulties experienced by our hauliers and the wider community.”
He went on to call on the Secretary of State for Northern Ireland, Government and the EU to “modify the bureaucratic regulations”.
Mr Beggs continued: “The barriers imposed inhibiting trade between Northern Ireland and our main suppliers and customers in the rest of the UK are already proving costly to the haulage sector and local businesses. The processes are affecting the local economy. Additional costs will be ultimately passed on to consumers.
“This is an urgent matter as even more burdensome processes are due to be introduced on the 1st of April and the 1st of July when exemptions come to an end.”
Click here to read: Call for ‘Freeport’ to be established in Larne
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