Clean-up operation after gangs of young people set cars on fire, Mayhill area of Swansea, Wales UK. 

Clean-up operation involving local people and Council workers after gangs of young people set cars on fire and rolled them down a hill in the Mayhill area of Swansea, Wales UK.
Footage of the incident has been circulating on social media.
South Wales Police say they "attended a large scale disorder" but locals claim that police arrived almost four hours later.