A large gathering of more than 100 people took over a city car park on Sunday evening.
Around 60-70 cars appeared to be gathered at near PC World at Newport Road Retail Park, Cardiff, revving their engines and driving up and down along Newport Road.
One woman, who didn’t want to be named, said: "I just drove past. There were well over 100 kids gathered there hanging around. It was pretty scary to be honest."
It comes after scenes of 'hostility' last month as police faced crowd of hundreds in Cardiff. You can read about that, here.
Another witness at the scene said it felt like a "sinister atmosphere".
They added: "More than 100 young people have gathered in the car park of PC World and Tops Tiles on Newport Road.
"What appears to be a car meet, I've seen about 60 cars many of them modified, parked all over the car park and opposite. Young people between the ages of about 16 and 25 can be seen gathering around the main highway into Cardiff running across the busy six carriageway road.
"Cars are revving up and down the road as well as within the car parks.
"A few of the cars seem to be drag racing up and down the road. Several police cars have driven by but not stopped."
South Wales Police was approached for a comment.
