Massive amounts of cocaine have mysteriously washed up on shores south of Tokyo in Japan’s biggest drugs haul, police said.

Local residents in Yokusaka, Kanagawa Prefecture, found suspicious backpacks on the beach Thursday which were later revealed to contain roughly 80 kg (176 pounds) of cocaine.

The four bags, attached to a float and plastic bottles with glow sticks, were reportedly stuffed with 78 blocks of cocaine wrapped in waterproof tape.

Officials have put the street value of the haul at an estimated 4.8 billion yen ($48 million).

Another two bags were found containing about 40 kg of cocaine, putting the total amount of the drug haul to 120 kg and the value to a whopping $72 million. The seizure was thought to be the biggest discovered in the country, public broadcaster NHK said.

It was suspected the bags were thrown overboard after a drug deal failed at sea but a spokesman for the police declined to comment.

Japanese police seized just 6.6 kg of cocaine last year, down from 28.7 kg in 2011, according to the National Police Agency.

By Maesie Bertumen

Image: Sebra /