Ibrahim Badreddin Al Houthi, the brother of Houthi leader Abdulmalik Al Houthi, has been assassinated, several outlets reported.
Reuters, quoting a Yemeni security source, said the senior leader was found dead in a house near the capital, Sanaa.
The Houthi-owned Al Masirah channel announced the killing on Friday, saying "the treacherous hands affiliated with the US-Israeli aggression and its tools assassinated Ibrahim Badreddin Al Houthi".
But Al Alrabiya news station released its own detailed account of the killing, saying Ibrahim was assassinated in his car on Wednesday at 8pm while travelling from Omran to Sanaa.
It said the killing was an inside job in a battle between different Houthi wings, and the senior figure was killed along with nine of his guards.
Sources linked with the Arab Coalition said that he was killed in an air strike on the border
with Saudi Arabia.
Ibrahim was a de facto finance minister for the Iran-supported rebel movement.
A source in Sanaa told The National that the young Houthi leader was found dead in his house and attributed his murder to deep rifts among senior leaders in the Houthi movement.
“Frictions are behind the murder of Ibrahim Al Houthi,” the source said.
Ibrahim was the younger brother of Abdulmalik
He was born in Dhahyan district in 1982 and played a leading role in storming Sanaa, starting with a protest in August 2014.
He had been serving as a protective security head and was often seen accompanying his brother in Saada province, the main stronghold for the Houthi movement.
A source in Saada told The National that Ibrahim was the fourth son of Badreddin Al Houthi to be killed.
"Everybody in Saada knows that Badreddin Al Houthi has 13 sons from different wives – three have been killed in the wars with the Yemeni army since 2004," the source said.
His killing was mourned by at least one other Iran-affiliated group, Hezbollah.
"Hezbollah offers condolences to the Yemeni people and leadership and the leader Sayyed AbdulMalik Badreddin Al Houthi on the martyrdom of the Ansarullah commander Sayyed Ibrahim Badreddine Al Houthi," Hezbollah-owned Al Manar TV reported.
Yemen expert Fatima Al Asrar suggested in a tweet the plausibility of infighting within the group as reason for his death, claiming he was not on the Saudi coalition hit list.
The death comes as clashes intensified this week in the city of Aden between Houthis and government-allied forces.
On Thursday, the US urged against an escalation in violence and called for further bloodshed to be avoided.
Washington also called for differences to be resolved through dialogue.