Does anyone know what's happening in Central Cardiff this evening?

First we get this from one of our stringers:

"Centre of Cardiff right now sounds like the apocalypse is kicking off - helicopters, big bangs, police sirens and people shouting - guess this is a normal wed night?"

and then we get sent this photograph



With the comment:

"hi mate there were helicopters flying all over head tonight... and about 5 mins ago 11.40 pm the cops threw a few kids in the back of the meatwagon....
i think they were joyriders.... this is just off Westgate St"

The South Wales Police site helpfully reports:

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