British army technical officers are examining a suspicious object in north Belfast, the PSNI said.
A spokesman said the object was discovered in Glenbryn Park in the north of the city. The area has been the scene of some of the most bitter sectarian clashes over the summer.
Overnight, homes on the Ballygally Road near Dungannon, Co Tyrone, were evacuated due to a security alert. The road was closed and the British army examined a suspect vehicle some time before 4 a.m.
No signs of a device were found, and residents were allowed return to their homes two hours later.
Two main roads in Randallstown, Co Antrim, were closed this morning because of a security alert that turned out to be a hoax. Main Street and Church Road were closed after the discovery of a suspicious object.
However, after examination, the suspect device was declared a hoax and the roads were reopened.