Yemen's Iran-backed Houthi rebels hijacked a ship in the southern Red Sea, according to the state-run Saudi Press Agency. The move came as Yemen's internationally recognized government returned to the country for the first time since being forced out by the southern separatists last summer.

The tugboat "was hijacked and subjected to armed robbery by terrorist elements affiliated to the Houthi militia," a spokesman for the Saudi-led coalition, Turki al-Malki, said.

Yemeni Foreign Minister Mohammed Abdullah al-Hadrami condemned the seizure of the vessel, which was being used to tow a South Korean drilling rig, as " provocative and illegal."

A South Korean Foreign Ministry official announced Tuesday that there were three vessels seized by the Houthi rebels and that two of them are South Korean ships.

The Houthis have routinely targeted oil rigs, usually those belonging to Saudi Arabia or its coalition partners that have been supporting the Yemeni government since in 2015.

On Monday, rebel leader Mohammed Ali al-Houthi had said that the "Yemeni coast guard is doing its job" and was trying to determine if the seized vessel "belongs to the aggressors or to South Korea."

"If it is for South Korea, they will be released after legal procedures," he said.

Peace within grasp?

At the same time, Yemeni Prime Minister Maeen Abdulmalik Saeed returned to the key southern port city of Aden as part of a power sharing deal brokered by the Saudis that is meant to bring an end to the bloodshed.

"Today we are uniting our efforts to defeat the Iranian project in Yemen and restore the state,'' the government said in a statement.

Saeed was one of five ministers from President Abed Rabbo Mansour Hadi's government to arrive on Monday, with the rest of the administration due to join them the following day.

"The government's priorities in the next stage are to normalize the situation in Aden first and then consolidate state institutions on the ground ... as a guarantor of stability,'' Saeed told The Associated Press.

The conflict in the Arab world's poorest country began in 2014, when Houthis took control of the capital, Sanaa, and captured much of Yemen's north. More than 100,000 people have died in the war and millions have been displaced, leading to widespread humanitarian crises such as a lack of food and medicine.

es, mvb/aw (AP, dpa, Reuters)

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