Yemen's Iran-backed Houthi rebels took full control of the Bab el-Mandeb Friday when they captured a Red Sea island located in the middle of the vital shipping lane, a local government official and eyewitnesses said.

"Boats carrying armed Houthi fighters reached Mayyun Island after government forces withdrew from it yesterday," the official said, referring to an island also known as Perim that divides the strait into lanes.

"The Houthis have completed their takeover of the Bab el-Mandeb area and Mayyun Island, which is located in the middle of the strait," he added, speaking to Agence France-Presse (AFP) on condition of anonymity.

An eyewitness said gunmen were "deploying along the Bab el-Mandeb shore and are driving around in military vehicles."

Hundreds of people have died since the Iran-backed Houthis launched an offensive around Bab al-Mandab, a vital artery for Saudi oil exports.