DUBAI, United Arab Emirates (AP) — A mysterious airstrip being built on a remote island in Yemen is nearing completion, satellite photos analyzed by The Associated Press show, one of several built in a nation mired in a stalemated war threatening to reignite.

The runway is likely built by the United Arab Emirates, which has long been suspected of expanding its military presence in the region and has backed a Saudi-led war against the Houthis.

While the Houthis have linked their campaign to the Israel-Hamas war in the Gaza Strip, experts worry a ceasefire in that conflict may not be enough to see the rebels halt a campaign that’s drawn them global attention. Meanwhile, the Houthis have lobbed repeated attacks at Israel, as well as U.S. warships operating in the Red Sea, raising fears that one may make it through and endanger the lives of American service members.