BANGKOK (Reuters) - Thai police have seized nearly $21 million worth of assets, from cars to cryptocurrency, belonging to the late founder of dark web marketplace AlphaBay, who died in a Bangkok jail this month, they said on Monday.

Alexandre Cazes, a 25-year-old Canadian citizen, was arrested in Thailand on July 5 at the request of the United States.

Thai police on Monday confirmed he was the administrator of AlphaBay, an online site devoted to the sale of illicit goods, ranging from computer hacking tools to drugs and weapons.

AlphaBay was widely considered the biggest online black market for drugs, estimated to host daily transactions totaling hundreds of thousands of dollars.

Cazes was found dead in his cell at the Narcotics Suppression Bureau in Bangkok on July 12 before he was due to be extradited to the United States, deputy national police chief Chalermkiat Sriworakan said.

“We have seized over 700 million baht worth of assets, cars, and cryptocurrency,” Chalermkiat told Reuters. The sum is equivalent to $21 million.

Cazes faced charges related to narcotics distribution, identity theft, money laundering and other crimes.

It was unclear if Cazes had been provided a lawyer or if police had appointed one for him, as is sometimes the case in Thailand.

His Thai wife, Sunisa Cazes, also faces a money laundering charge. She is in custody and Reuters was unable to reach her for comment.

Cazes, referred to as “DeSnake” by some in the online community, operated chiefly from Thailand, where media said he owned several properties and had connections in many countries.

His arrest followed a police operation called Bayonet, which involved authorities in six countries including the FBI, the Dutch National Police and the Royal Thai Police.

AlphaBay was “the largest dark net marketplace in history”, U.S. Attorney General Jeff Sessions said last week, when he announced its shutdown by the U.S. Justice Department.

(This story has been refiled to fix police official’s name in paragraphs 5, 6)