The man was detained by officers while in his motor boat in the Kitovy Bay in the Sea of Japan with four sacks full of sea cucumbers.

"This is the biggest ever seizure of sea cucumbers by customs officers," a spokesperson for the FSB Border Service said.

Sea cucumbers, also known as trepangs, are not in great demand in Russia, but people eat and use them for medicinal purposes in Japan, China, and other Asian countries. A kilogram of dried trepang costs $220-250 in China.

The commercial catching of trepangs is prohibited in Russia. However, poachers are often detained in the waters of Russia's Far East. In October, a total of 2,300 live sea cucumbers were seized in Russia and later released back into the sea.