The government began to perform the next stage of land reclamation work in Okinawa Prefecture on Monday, as part of a project to build a replacement facility for a contentious U.S. air base in the prefecture despite local opposition.

The work to pour soil and sand into a new 33-hectare section off the coast of Nago's Henoko district began in the afternoon, moving the construction plan for U.S. Marine Corps Air Station Futenma into a new stage even though a prefectural referendum last month showed more than 70 percent of residents oppose it.

The area in which land reclamation work is being carried out is next to a 6.3-hectare section that started being filled in during December. The landfill work is required in order to relocate the base from Ginowan to Nago.