A group of people in Okinawa, Japan have sued to block the reclamation of land for a US Marine base.

Coastal waters off the island’s north are to be filled in so the Futenma US Marine station can be relocated from an urban area.

The governor of Okinawa approved the long-stalled project last month, but many locals want the Futenma base moved entirely off-island.

Almost 200 people taking part in the suit say the plan breaks laws governing reclamation of public waters, and doesn’t pay sufficient heed to the environment.

They are demanding that Okinawa Prefecture reverse the decision.

They are also asking that work not begin while their suit is being considered.

The suit could prove to be yet another stumbling block in the plan to realign the US military on Okinawa.

The island is key to US-Japan security ties, but the heavy US military presence there has long been opposed by many Okinawans.