Saudi Arabia, and other countries within its coalition, allegedly gave fighters linked to al-Qaeda waging war in Yemen American-made weapons, which were also given to a Salafi militia headed by at least one member with ties to a Yemeni branch of ISIL.
The investigation also found that United States weapons also made their way into the hands of Iranian-backed rebels who are battling the Gulf coalition for control of the country, exposing some of America's sensitive military technology to Tehran.
The United States foreign affairs committee chairman has said on Wednesday he heard stressful reports of Saudi Arabia supplying and transferring armed weapons to the extremist militant groups in Yemen and questioned whether the US Congress should further consider imposing some more restrictions over weapon sales to the Saudi Arabia-led coalition. A US defense official confirmed to CNN there is an ongoing investigation into the matter.
As chairman of the House committee, Engel has the right to review and put "holds" on major foreign weapons sales, Reuters reported.
Democratic congressman Eliot Engel, who chairs the US House of Representatives' Foreign Affairs Committee, said on Wednesday he was troubled by reports about illicit weapons transfers in Yemen. "We can not look the other way when it comes to the recklessness with which the Saudi-led coalition has conducted its operations".More news: Twitter profit soars as user base shrinks
The Department of Defense asserts that Saudi is breaking the terms of its arms sales with the United States by handing off military equipment to third parties.
The weapons - including anti-tank missiles, armored vehicles, heat-seeking lasers and artillery - have been passed on, sold, stolen or abandoned in Yemen.
Senators, including prominent Republicans, inflicted a resounding rebuke to the president in December, holding the Saudi crown prince responsible for the murder of Jamal Khashoggi after the Trump administration had been largely supportive of Prince Mohammed bin Salman.
President Donald Trump's administration opposed numerous bills, calling the Saudis important regional partners and praising weapons sales as an important source of U.S.jobs.
Starting under the Obama administration in 2015, the Pentagon has provided logistical, targeting and intelligence support to the Saudi-led coalition in Yemen.More news: Galaxy Note S Pen might have a camera inside for selfies
"It can no longer be business as usual".
Late previous year, politicians introduced various pieces of legislation seeking to put tighter controls on USA dealings with Riyadh, including clamping down on weapons sales, barring military cooperation with the Saudi-led coalition and calls for human rights sanctions.
The US-Saudi war has killed thousands of civilians and also taken a heavy toll on the country's infrastructure, destroying hospitals, schools, and factories.
The Senate approved the measure in November over the Trump administration's objections. The then-Republican controlled House blocked a vote on a Yemen-related resolution.More news: Maurizio Sarri explains how Chelsea can beat Manchester City on Sunday