Police searches are ongoing at a number of properties in the Old Glenarm Road area of Larne.
It is understood the searches are in connection with the arrest of a man on suspicion of terrorism offences.
According to the Metropolitan Police, the man is a serving member of the British armed forces.
The 30-year-old was arrested in Somerset at 12:20pm this afternoon, August 24 by officers from the Metropolitan Police Service’s Counter Terrorism Command (SO15), supported by colleagues from Avon and Somerset and Devon and Cornwall Police, on suspicion of being involved in the preparation for acts of terrorism under section 5 of the Terrorism Act.
The arrest was pre-planned and intelligence-led as part of an investigation into Northern Ireland-related terrorism.
It was led by SO15 in collaboration with Police Service of Northern Ireland (PSNI) and the South West Counter Terrorism Intelligence Unit.
No armed police were involved in the arrest.
The public can be reassured that there is no intelligence to suggest an immediate threat to our communities.
The man was arrested at an address in Somerset and has been taken to a West Country police station.
Searches are being conducted by SO15 and local uniform officers under Schedule 5 of the Terrorism Act at an address in South Devon.
Further searches are taking place in a wooded area in south Devon, which has been cordoned off, and by PSNI in Northern Ireland in connection with the inquiry.