Image copyright Reuters Image caption Tens of thousands of people joined the protests

Tens of thousands of demonstrators have gathered on the Japanese island of Okinawa to protest against the heavy US military presence there.

The protestors are angry after a former US Marine employed as a civilian worker was arrested over the rape and murder of a local 20-year-old woman.

The case has intensified longstanding opposition to the military bases, spurring calls for US military personnel to be moved off the island.

There are 26,000 US troops on Okinawa.

They work and live on bases that cover a fifth of the island and are a key part of the US-Japan security alliance.

The demonstration on Sunday began with a moment of silence for Rina Shimabukuro, the murder victim, and a message from her father.

"Why my daughter, why was she killed?" said the message, read on his behalf. "My thoughts are the same as those of all the bereaved families that have met with suffering up to now."

Image copyright AFP Image caption The demonstration on Sunday began with a moment of silence for Rina Shimabukuro

Anger simmers over Okinawa base burden

Protestors waved placards reading "Our anger is past its limit" and "Pull out the Marines".

Chihiro Uchimura, 71, told the AFP news agency: "I'm filled with sadness and I really don't want any more victims."

"As long as there are US military bases this kind of incident will continue to happen," she said.

A simultaneous demonstration was held outside the Japanese parliament in Tokyo.

Image copyright AP Image caption The US Futenma airbase is located in a densely populated area

A 32-year-old US civilian working at the base was arrested last month in connection with the murder of Ms Shimabukuro.

The demonstrators called for the scrapping of plans by Washington and Tokyo to move a major US Marine facility in the centre of the island to a more remote area.

Okinawa's Governor Takeshi Onaga, who attended the rally, is opposed to the plan and wants the base removed entirely.

The decision to move the facility was sparked by the rape of a 12-year-old Japanese girl by three US servicemen in 1995.

But the plan has been delayed by local opposition and legal manoeuvring.

Okinawa was under US occupation for 27 years, following World War Two.