An 11-year-old boy is still in hospital after an eight-vehicle crash in the Swansea Valley.
The incident closed the A4067 between Pontardawe and Glais for most of the day on Tuesday after eight vehicles collided on the southbound carriageway at 8.30am.
Seven cars and a coach were involved in the crash and an 11-year-old boy, who was in a Vauxhall Corsa, was taken to the University Hospital of Wales in Cardiff by air ambulance.
Police confirmed that "numerous" other people received minor injuries.
A 75-year-old man who was arrested in connection with the incident has been released under investigation.
A spokesman for South Wales Police said: "We are still appealing for witnesses following a serious road traffic collision at approximately 8:30am yesterday on the southbound carriageway of the A4067 between Pontardawe and Glais.
"The 75-year-old man who was arrested in connection with the collision has been released under investigation.
"An 11-year-old boy remains in hospital in a serious but stable condition.
"The A4067 was closed in both directions between Glais and Pontardawe for many hours to allow for vital investigative work to be carried out, and officers would like to thank the local community for their patience and understanding.
"We would like to speak to any witnesses who may have left the scene prior to giving their details to officers, and anyone who may have dash-cam footage of the collision, or of any of the vehicles involved prior to the collision."
Anyone with information about the incident is asked to contact the serious collision investigation unit on 101, quoting reference 1900200890.
