The army bomb squad in the North is involved in a number of ongoing operations, which have led to homes being evacuated.
A suspect device is believed to have partially exploded under a parked car at St James Road in west Belfast, shortly before midnight
It caused extensive damage to the car. A number of residents have been evacuated and a section of the road is closed.
Homes have also been evacuated in the vicinity of North Queen Street and Great Georges Street in north Belfast, following the discovery of a suspicious object.
There is a similar operation underway at Friendly Street in south Belfast.
Meanwhile bus transfers are operating between Newry and Belfast due to a security alert affecting the Dublin to Belfast Railway line at Lurgan.