Thailand's navy on Monday began towing to shore the floating cabin of a fugitive U.S. citizen and his Thai girlfriend, both prominent members of the "seasteading" movement who face possible death sentences for setting up their offshore home.

The cabin set on top of a spar 14 nautical miles off the Thai island of Phuket had been touted as a milestone in the movement to build floating communities in international waters as a way to explore alternative societies and governments.

Authorities have revoked the visa of bitcoin trader Chad Elwartowski, 46, and charged him and his partner, Supranee Thepdet, with violating Thai sovereignty, punishable by the death penalty or life in prison.