Police are hunting an armed gang involved in a violent disturbance.
South Wales Police has issued images of the people they want to speak to after it was filmed on a mobile phone on Brecon Road, Merthyr Tydfil, on Monday.
It involved up to eight men who were carrying weapons, said the force. A 29-year-old has been arrested.
"This was a violent incident which is likely to have involved individuals who are known to one another," said Insp Jonathan Duckham.
"Our investigation into the incident is well under way and I hope people come forward to help us identify those involved.
"We have deployed officers in the area to reassure residents."
It is not yet known if anybody has been injured, said the force.