Snakes and Ladders play area was shut down for several hours after police swooped to investigate the incident in Houghton Regis, Beds.
The huge indoor complex has a three-tier play frame connected by slides, tunnels, rope climbs and ball ponds for kids aged 12 years and under to explore and have fun.
Officers shut down the playground have launched an investigation into an act of “child-on-child” bullying after the child’s mum rang to report the crime.
“Whilst they investigated on site, the playcentre was temporarily closed and we reopened after two hours.”
However, a woman claiming to be the angered mum of the alleged victim, has criticised the play centre.
She said: “Can I just say, this was my daughter and it was not “bullying” and you did not call the police! WE called the police. WE asked for the frame to be evacuated.
“WE asked for lock down, and YOU did not ask for any contact details for us so I have no idea how you think you are going to ever contact us about this.”
A spokesman for Bedfordshire Police said: “We were called on Tuesday (February 16) to reports of a suspicious incident at a children”s play centre in Houghton Regis, Beds.
“Officers attended and inquiries were carried out, suspending business for part of the day.
“An investigation into the circumstances of the incident has been launched and anyone with information is asked to contact Detective Constable David Elias on 101.”
Snakes and Ladders has been contacted for comment.