More than 100 people called police in Northamptonshire to complain about Halloween trick or treating.
Police said most of the calls were from elderly people, who reported youngsters throwing lit fireworks in the street and at a car.
Officers could not respond to all the calls, while there were reports of several small fires in Cambridgeshire.
The fire service had to deal with rubbish and wheelie bins being set alight along with numerous bonfires.
Inspector George Cooper of Northamptonshire police said his main concern was the safe handling of fireworks.
"Someone is going to get seriously hurt unless this matter is brought under control," he said.
"I appeal to all parents between now and 5 November to identify where your children are in the evenings."