The paramedic was attacked on board an ambulance

A paramedic suffered a broken rib after a group of youths boarded the vehicle and attacked him and a technician in the Grangetown area on Saturday night.

Two 16-year-old boys, a 17-year-old and a 19-year-old man have been arrested in connection with the attack.

A 23-year-old man arrested on Tuesday has been released without charge.

The ambulance service said a group of youths boarded the vehicle at around 2350 GMT. The paramedic also suffered facial attacks and the technician was treated for shock.

The crew were able to alert police by pressing a panic button on board the ambulance.

Panic button

Another ambulance crew was sent to assist and they took the two men to the University Hospital of Wales in Cardiff.

Police are appealing for witnesses who were in the street to help

They were later discharged from hospital.

South Wales Police said a 17-year-old youth has been arrested and bailed pending further enquiries.

Two 16 year-old boys and a 19-year old man have been arrested and are currently in custody.

No further action is to be taken against the 23-year-old man arrested on Tuesday.

South Wales Police are appealing for witnesses.

DI Paul Andrews said "We have conducted a thorough investigation and believe there is still one man outstanding who was involved in the assault."