Udon Thai police late on Friday night seized about 80 motorbikes and rounded up a number of youngsters for illegally racing on public roads.
Pol Col Phumwit Vechkama, the Muang district police superintendent, said the action was taken in responding to complaints that young motorcyclists gathered and raced on public roads around the Udon Thani township, causing public annoyance and safety risks.
About 100 policemen were deployed to round up the illegal racers.
Their motorcycles were seized and would be checked to see if they were stolen items.
Their parents were contacted to bring ownership documents before taking the vehicles back, he said.