A MYSTERY bang left residents unable to leave their homes for two hours as police tried to find the cause.

Members of the emergency services set up an exclusion zone around Riverside Road and North Cray Road, Sidcup, after reports of an explosion at about 9pm last night.

Residents were told to stay in their homes and keep away from the windows as a police helicopter scanned the area with a thermal-imaging camera.

After two hours they found no sign of any explosion, despite reports of a loud bang that shook the windows of the houses.

Eight fire engines attended the incident as well as a large police presence, but the cause of the noise remains a mystery.