ROME (AFP) - Italian police have broken up a drug gang that offered a drive-through service for cocaine just outside Rome's main cemetery, an operation that allegedly ran with the help of three corrupt cops.

"Customers... mostly by car and without even getting out, used to approach subjects posing as flower sellers, pay what was due and receive the quantity of drugs required," police said in a statement on Tuesday (June 8).

Twenty-two people were investigated as part of "Operation Cleopatra" following investigations by anti-mafia prosecutors.

Half were placed in pre-trial detention and another six put under house arrest.

It was not clear if the police officers, accused of being on the dealers' payroll, were among those arrested.

The suspects are accused of offences including criminal association aimed at drug trafficking, drug dealing, illegal possession of firearms, aggravated theft, corruption and breach of police records.

Dealers - mostly Egyptians who met in a cafe called Cleopatra - hid drugs in flower pots, in a flowerbed, or in bushes near their stall by the Flaminio cemetery north of the Italian capital, police said.

At night, they would move their business to a nearby train station, and also dealt drugs from a butcher's store. According to investigators, the group made as much as €20,000 (S$32,200) a day from their trade.

The Flaminio cemetery, Italy's largest, made the news in April following complaints it was failing to process hundreds of bodies.

According to funeral homes operators who staged a public protest, the backlog was due to a coronavirus-related surge in deaths, which exacerbated a pre-existing problem with insufficient cemetery capacity.