The gun was discovered during an outdoor play session organised by North Deal Community Park Association
Nine year-old Courtney Friend was playing at a special giant games afternoon at North Deal Recreation Ground when she tripped in some long grass and landed on a rusty air pistol.
The Sandown School pupil, of Northwall Mews, also discovered a Stanley knife with blade close by, next to the wall of the industrial unit.
She has been praised by Emily Barnes, chairman of North Deal Community Park Association, which organised the event, for alerting adults quickly. But Mrs Barnes is bothered the police took so long to come.
She added: “I called the police via 101 at 2.30pm. We were told not to touch and asked not to leave and that someone would be there within the hour.
“We called again at 3.30pm. This time we contacted the PCSO who advised us to ring 999 which we did.
“We were told someone would be sent over. Finally – at 6.15pm – the police arrived and took the gun and knife away.
“We were all very concerned with what seemed a very delayed response from the police to dealing with this incident, especially as it did not take long for a large number of local children to come looking for the interesting new find.”
Jean Friend, Courtney’s mum, and Sherry Freeman stayed with the weapons until the police arrived.
Jon Green, spokesman for Kent Police, said: “When the gun was found on the edge of the playing field in Western Road, Deal there were no perceived direct threats to the safety of the public.
“Officers were dealing with a very high volume of calls that afternoon and responding to other emergency incidents in the area, which prevented them from attending sooner.”
Mr Green added: “We are grateful to the members of the public who stayed with the gun until officers arrived to take it away and dispose of it safely.”