More than 100 killings took place in a three-year period after the UAE took security responsibility for the south of the war-torn country, where Al-Qaeda was gaining ground, the British broadcaster said.
The oil-rich Gulf monarchy is a key member of the Saudi-led coalition formed in 2015 to fight Yemen’s Iran-backed Houthi rebels, who control most of the country’s north.
Many of those killed were members of Islah, the Yemeni branch of the Muslim Brotherhood – the Islamist movement banned in several Arab countries including the UAE, the BBC said.
However, the UAE denied carrying out any assassinations not linked to terrorism.
“The allegations concerning the targeted assassination of individuals with no links to terrorism are false and without merit,” a UAE official said in a statement sent to AFP.
“The UAE has supported counter-terrorism operations in Yemen at the invitation and with the knowledge of the government of Yemen and its international allies.
“The UAE has acted in compliance with applicable international law during these operations.”
The BBC interviewed a former US navy Seal, later the head of a private security company, who said he was one of several Americans hired by the UAE to carry out killings.
His missions included the attempted assassination of Ansaf Mayo, a Yemeni politician and Islah leader in Aden, the temporary home of Yemen’s government.
US mercenaries also trained Emirati officers who in turn coached Yemenis to carry out killings, making it harder to trace them back to the UAE, the report said.
The investigation cited “more than a dozen” Yemeni sources who confirmed the allegations, including two men who said they were trained by Emirati soldiers to carry out assassinations not linked to terrorism.
The UAE said similar allegations have been made in the past, “which have already been shown to be untrue and politically motivated”.
“Should any new, possibly credible allegations come to light in the future, the UAE will of course conduct rigorous investigations,” the official said.
The UAE has also recruited former Al-Qaeda members – including a suspect in the deadly 2000 attack on the USS Cole – for a force formed to fight the Houthis and conduct assassinations, the BBC said, citing a whistleblower and a Yemeni government minister.