Saleh al-Sumad, the head of Yemen's Houthi movement's politburo, delivers a speech at a ceremony during which a political council to rule the country was announced in Sanaa, Yemen Aug. 6, 2016. (Reuters photo)

SANAA, April 23 (Xinhua) -- Yemen's dominant Houthi rebels on Monday announced that their top official, President of the Supreme Political Council Saleh al-Sammad, was killed in an air strike by the Saudi-led coalition in the Yemeni Red Sea port city of Hodeidah, according to a statement carried by Houthi-controlled state Saba news agency.

They said al-Sammad was killed, at the age of 39, on Thursday in Hodeidah city. Houthis vowed to revenge his death, said the statement, which provided no further details on the circumstances of his death.

Also in the statement, the Houthis declared appointment of Mahdi al-Mushat as new president of the Supreme Political Council, which is the highest political and ruling body since Houthis seized control over much of the country's north.

In September 2014, al-Sammad was appointed as an advisor and representative of the Houthi group in the presidential office of President Abd-Rabbu Mansour Hadi.

Five months later, Houthis stormed the capital Sanaa and forced Hadi and his government into exile.

On Aug. 6, 2016, al-Sammad was appointed by his group as President of the Supreme Political Council.

Al-Sammad had served as a teacher of Islamic teachings before he was pushed by his group into the political stage in 2014.

Saudi Arabia had offered 20 million U.S. dollars for any information that leads to his capture or killing.

The coalition considered al-Sammad as the No. 2 leader after the group chief Abdul-Malik al-Houthi.

The killing of al-Sammad is considered the most powerful blow so far on the Iranian-backed Houthi movement.

The coalition intervened in the Yemeni conflict in March 2015 to roll back the Iranian-allied Shiite Houthi rebels and support the internationally-recognized President Hadi.

The rebels have seized control over much of the country's north since September 2014, including the capital Sanaa, and forced President Hadi and his government into exile in Riyadh, the capital city of Saudi Arabia.

The war has killed more than 10,000 Yemenis, mostly civilians, and displaced 3 million others, triggering one of the world's worst humanitarian crises.