Byron Bay Police Duty Officer, Inspector Ian Fitzsimmons, said he was disappointed with the "antisocial" Halloween behaviour of a group of young people at Suffolk Park over the weekend.
Inspector Fitzsimmons said 40 to 60 young people were "running around" Suffolk Park on Saturday night throwing eggs, flour bombs and water bombs at cars and houses.
Inspector Fitzsimmons said garbage bins were set alight and a window at the Suffolk Park Medical Centre was smashed.
He said police patrolled the area but the darkness helped the young people elude them.
No charges were laid, he said.
Said Inspector Fitzsimmons: "It's very disappointing that this sort of anti-social behaviour continues.
"Again I ask the question, where were the parents?"
Halloween in Mullumbimby last Saturday was a great party according to everyone involved.
Between 250 and 300 children up to the age of 12 turned out in devilish costumes and played games and 'had a ball.'
Kim Mitchell, one of the organisers of the Chamber of Commerce sponsored event, said this was the biggest Halloween party they had staged so far.