No damage or injuries were reported.

Police said a metal object containing “a small amount of pyrotechnic material” exploded about 30m away from a perimeter compound of the embassy, which lies in a heavily populated area of Nicosia.

Four youths aged between 17 and 21 found in the area were being questioned by police, a security source said.

In the car of one of the detainees police found two knives and a hammer.

Cyprus state radio reported the detainees were Syrians.

Cyprus, on the edge of the volatile Middle East, has tightened security at locations across the island.

In the wake of fresh violence authorities widened a security cordon around the embassy, shutting off civilian roads.

The embassy was the target of a botched bombing attempt in 1988 when a car packed with explosives went off on a nearby bridge, killing three people.