On a single Saturday night, one London council confiscated more than 1,200 canisters of laughing gas, while other local authorities are seizing "hauls" of the chemical, according to the Local Government Association.
Hackney Council in east London said that it took the small metal containers outside the pubs and clubs in Shoreditch on a Saturday night last month.
Officials in Norfolk, Hertfordshire and Thames Valley have reported increasing numbers of cannisters being found.
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