Scotland Yard has seized almost £10m of heroin in Finchley, north London.
Three men were arrested after officers thwarted a transfer of two holdalls full of the class A drug between two vehicles.
Officers from the Metropolitan Police Service's Middle Market Drugs Partnership had a Mercedes car under observation as it stopped in Tarling Road on Sunday, 14 September.
The male driver met an Audi car and a white van and was seen to remove two black holdalls containing around 40 kilos of heroin from his car before putting them into the van.
It was then that officers swooped and arrested three men, aged 33, 36 and 48, alleged to be involved in the exchange. All remain in custody.
Officers then found another two kilos of the drug and around £10,000 in cash during a subsequent search of an address in north London.
In total, the street value of the heroin seized would be around £9.5m.