Devon and Cornwall Police has apologised for selling nitrous oxide - known as 'hippie crack' - on eBay.
The force listed boxes containing 24 8g canisters of nitrous oxide for £10, with free delivery. They were being sold via an account used to dispose of unclaimed lost property, seized items and the like that raised £12,000 in its first ten months.
But while the canisters have a legitimate use in catering and are marketed for use powering whipped cream dispensers, they are also used to get high.
But while the effects have led to the nickname laughing gas, they can also include hallucinations; and if too much is taken, it's even possible for lack of oxygen to lead to death.
The listing is all the more outrageous given that the force has had a problem with nitrous oxide for years.
It put out warnings about the danger of the gas in 2012 and 2015, after empty canisters were found lying around.
"They don't come without danger, and numerous deaths have been linked to their use in recent years," PCSO Phil Thomas said at the time.
"Police advice is not to use them and I suggest parents may like to research the internet and acquaint themselves with nitrous oxide capsules, which are freely available online."
The eBay listing was spotted by the Feed The Birds Facebook group: "You know the war on drugs has failed when your local police force are also the local drug dealers," commented one member.
The force has now apologised, and has removed the remaining canisters from sale. It points out that the listing did contain a warning about misuse of the canisters.
"Devon and Cornwall police has a responsibility to dispose of seized and excess items in the most cost-efficient way possible, but it is not force policy to sell items that are viewed as contentious by the public," a spokesperson told the Plymouth Herald.
"On reflection, we regret placing these items for sale. Our force policy has been revised to ensure these items are destroyed and not sold. All similar items have been withdrawn from sale."