A 59-year-old man has been arrested on suspicion of possession of a firearm with intent to cause fear or alarm after an incident at a polling station in Co Tyrone.
The man has been taken into custody for questioning and further searches as part of the investigation are ongoing.
UUP West Tyrone candidate Chris Smyth claimed a man with a gun threatened voters at a Greencastle polling station in Co Tyrone.
Police confirmed they received a report of a man acting suspiciously at a polling station on the Crockanboy Road, Greencastle.
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"It was reported that the man may have been carrying a firearm," a PSNI spokesperson said.
"Efforts are continuing to locate him and enquiries into the matter are ongoing."
The PSNI have said they do not believe anyone was threatened during the incident.
Chief Electoral Officer for Northern Ireland Virginia McVeigh is planning to attend the polling station in Greencastle.
She said that a handgun had been pulled on staff working at the station.
Councillor Smyth said he was informed by police a man walked into the polling station with what appeared to be a handgun and saying he would shoot voters.
"I am shocked and appalled that something like this could happen," he said.
“I am informed there were no police present at the time. I arrived just 10 minutes later and there is now a strong, armed police presence at the scene.
“It is sad that we continue to have people in our society who want to terrorise and intimidate you just because of your political opinion. These people need removed from society. I for one will not be intimidated by them.”
It is understood electoral officers have asked for additional police support at the polling station.