TOKYO (AFP) - A haul of cocaine with an estimated street value of US$48 million (S$60 million) has washed ashore on a beach south of Tokyo, reports said on Thursday, with authorities suspecting seafaring traffickers.

An elderly local resident found 80kg of the drug inside backpacks that were tied together and reported it to police, Jiji Press and other media said.

The bags were outfitted with a buoy and illuminated markers and authorities suspect that they were lost by seafaring traffickers, the reports said.

Local authorities declined to comment on the reports when contacted by AFP.