There are concerns that children under 12 years old in Crediton are experimenting with so-called laughing gas - which is highly dangerous.
Youngsters have been seen gathering in a den where nitrous oxide canisters have been found, among the trees in Newcombes Meadow.
There were also empty sweet packets, drink containers, balloons and lighters.
There was also a school book which had been set on fire and would have belonged to a pupil at the junior level.
A local primary school has been informed, along with the police.
The use of nitrous oxide has been a problem in the town for some time - police are warning that it's habit forming and addictive, and can even kill.
Parents are being urged to make sure they know where their children are when not at school.
Decision on Devon’s bid to delay election expected soon
21 homes in Honiton approved despite objections
Plymouth online group boosts free dental care uptake
Police tax to rise next year
Proposal to sell ‘vital’ Tiverton canal building delayed
Housebuilder receives permission for Cranbrook sales office
