Image copyright Reuters Image caption Gunmen sprayed the bus with bullets and then escaped

At least seven people were killed when gunmen in Sri Lanka opened fire on a prison bus outside Colombo.

Police said five inmates and two guards died in the attack near the town of Kalutara. Nine others are in hospital.

The bus was transporting a prominent underworld suspect and other prisoners to court.

Police say the shooting resulted from a feud between two gangs. The gunmen escaped after spraying the bus with bullets.

Image copyright Sri Lanka police Image caption Aruna Damith Udayanga had been accused but not convicted of several murders

Among those killed was Aruna Damith Udayanga, alias Samayan, who police say was a major underworld figure.

The BBC's Azzam Ameen in Colombo says the shooting is the single deadliest of its kind in Sri Lanka for years.

There have been a number of shootings targeting prison buses.

Another suspected gang leader was injured in a prison bus shooting in the capital last March.

Police set up roadblocks after six people were killed in two separate incidents on that day, AFP news agency reports.