Part of the Upper Newtownards Road has been closed between the Knock traffic lights and Cabin Hill Park on Sunday afternoon.
A number of homes have been evacuated, with Stormont Presbyterian Church made available for those affected.
Police area the scene and diversions are in place.
Police are currently attending a security alert at Upper Newtownards Rd in East Belfast. Part of the road is closed, diversions are in place
More top news
Some Scottish social media users were left confused when Facebook offered them a Romanian flag, not a Saltire, to mark St Andrew's Day.
Ex-detectives Michael Stokes and Stephen Phillips were jailed for two years for stealing money they thought belonged to a drug dealer.
The calendar famous for its pin-up style has taken a dramatic turn - eschewing supermodels for 13 women of "outstanding accomplishment".