TOKYO (AFP) -- A Japanese court on Saturday issued a warrant for the arrest of a 21-year-old U.S. Navy sailor suspected of killing a Japanese woman near a U.S. naval base in Yokosuka, a report said.

The Japanese government plans to ask the United States to transfer custody of the suspect, now in confinement on the U.S. base at the mouth of Tokyo Bay, to local police, Kyodo News said.

If the United States agrees to the transfer, police were expected to arrest the serviceman as early as Saturday.

Police in Kanagawa prefecture said Friday that the sailor, a black male crew member of the U.S. aircraft carrier Kitty Hawk, had admitted to killing 56-year-old Yoshie Sato near the base on Tuesday.

But the sailor has yet to reveal his motive for the alleged crime, Japanese semi-public broadcaster NHK reported.

Sato was found dead and bleeding from her head in the entrance of a building after apparently being attacked on her way to work in what may have been a robbery gone wrong, local media said.

Under a U.S.-Japanese accord, the U.S. military is not required to hand over suspects unless they are charged.

The US Navy said it was offering its full cooperation to Japanese police.

But the case was likely to reignite controversy over the U.S. military presence in Japan, as many communities are reluctant to continue hosting U.S. bases, largely because of crimes committed by soldiers and noise pollution.

There was also public outcry in November after Tokyo said it had agreed to host a nuclear-powered U.S. aircraft carrier for the first time in Yokosuka, the electoral district of Prime Minister Junichiro Koizumi.