Police are appealing for information after two men and two women were attacked on the Calzaghe Bridge in Newbridge in the early hours of Sunday July 6.
The victims were assaulted by four men as they walked across the bridge between 12.30am and 12.45am.
The two men suffered facial injuries and were treated at the Royal Gwent Hospital in Newport. The two women were unharmed.
One of the attackers was wearing an orange t-shirt and another was wearing a blue and white striped t-shirt. They were all white, of average build and in their late teens or early 20s.