Two youths were arrested and e-scooters seized after gangs of children caused havoc in Lancaster venues.
One group of children harassed staff and other young people at a local youth group on Friday night, said police.
Later, another gang harassed staff in food venues in Lancaster city centre, shouting abuse at them and customers and throwing items around.
Police made the two arrests and confiscated three of the youths' e-scooters.
"Your local neighbourhood officers last night were kept busy with a minority of local children who think it is appropriate to cause antisocial behaviour towards others," said a post on the Lancaster Area Police Facebook page.
"One group last night thought it was acceptable to attend a local youth group and instead of join in, harassed the staff and the other children who were trying to enjoy the activities put on for them.
"Later on another group in the city centre thought it was appropriate to harass staff of local food venues, shouting abuse at them and their customers and throwing items around the venues.
"As a result two youths were arrested for their unacceptable behaviour in the city centre and taken into police custody.
"Furthermore three of the youths had their e-scooters taken off them to be destroyed.
"We know most children are nice and respectable and it is the small minority who ruin it.
"But please if you are a parent make sure you know where your children are and what they are doing."


Controversial new housing plans near Lancaster given thumbs up
LISTEN: Plans revealed for 'permanent seasonal' Lancaster On Ice
Morecambe woman charged with murder following death of eight-week-old baby
Rescue after person stuck in mud in Lancaster
Hundreds expected at Eden Project Morecambe 'breaking ground ceremony'
Morecambe children's nursery announces plans to close during extreme heat
Lancaster MP responds to Sir Keir Starmer's resignation as Prime Minister
Carnforth High School praised as a "caring community" in Ofsted report
Body of man found in Lancaster park
LISTEN and PHOTOS: Armed Forces weekend will return after massive crowds enjoy biggest ever event
Morecambe MP says Sir Keir Starmer "has made right decision" as Prime Minister resigns
Limited edition artwork will raise vital funds for Lancaster community group
Green Heritage Plaque marks first home of Lancaster University
New home revealed for £20m Morecambe West End regeneration scheme
Wooden nests take flight in Lancaster and Morecambe to stop decline of endangered birds
Veterans salute as Armed Forces Day flag raised at start of celebration weekend in Morecambe
Vandals cause delays to aqueduct sinkhole repairs in Lancaster
Extra Care scheme to open in Lancaster
Three people taken to hospital after road traffic collision in Morecambe
Injured police officer speaks of anger after jailed man freed 16 days after sentence

