Police are appealing for members of a group to come forward to help with their enquiries after a box exploded in an underpass near a man and infant.

The incident, which is being treated as arson, happened inside the underpass in Old London Road, Copdock, at about 9.45pm on Wednesday.

A 29-year old man was pushing a buggy containing an infant when he saw a box containing a canister a distance in front of him. The box exploded, but the man and infant were not injured.

A group of about eight male young people ran from the scene shouting ‘sorry.’ The offenders left in three cars, one of which was thought to be a yellow Fiat Cinquecento.

One of the offenders is described as a white man, of a slim build, approximately 5ft 9ins tall and had dark-coloured cropped hair.

Police are appealing for any witnesses or a member of the group seen in the area at the time to come forward by calling 101, and quoting HD/13/1520 and asking for Sergeant Paul Heighway.