The FBI has rebuffed a formal request from Oregon’s senior U.S. senator and won’t turn over information it might have about a growing number of cases where students from Saudi Arabia vanished while facing criminal charges around the country.

The bureau delivered its decision several weeks after Sen. Ron Wyden asked Christopher Wray, the head of the FBI, about the cases during an open congressional hearing and later inquired in writing if the agency had evidence that the Saudi government provided assistance to the suspects. Their alleged crimes have included rape, manslaughter and felony assault.

“The FBI takes seriously the concerns you raised with FBI Director Wray … and in your letter, regarding allegations that a foreign power may have unlawfully assisted individuals in the United States to escape or avoid prosecution,” wrote Jill Tyson, the bureau’s assistant director of congressional affairs.

The bureau, however, “does not comment on the status or existence of any potential investigative matter,” Tyson said.

The response, dated March 7 but released Tuesday, is the latest received by Wyden, who has also asked detailed questions to the U.S. Department of Justice, State Department and Customs and Border Protection about the disappearances. All but Customs and Border Protection have issued short, written statements that provide little insight into a subject that’s generated national and international headlines.

“I have pressed on the administration in public and in private to explain this pattern of Saudi fugitives leaving the country,” Wyden, a Democrat, said in a statement. “With the exception of Customs and Border Protection, it appears no agency is willing to explain to Oregonians or the American people what’s being done in response to at least nearly two dozen individuals who have fled U.S. justice.”

Wyden began pressing the Trump administration for information after The Oregonian/OregonLive revealed criminal cases involving at least five Saudi nationals who disappeared from Oregon before they faced trial or completed their jail sentence, including those who had surrendered their passports to authorities.

The news organization has since found similar cases in at least seven other states — Montana, Ohio, Oklahoma, Pennsylvania, Utah, Washington and Wisconsin — and Canada, bringing the total number of Saudi suspects who have escaped prosecution to 25.

At least 22 of the suspects were attending universities in the U.S. and Canada. The Saudi Arabian government provided bail and legal fees to nearly all of them.

Federal law enforcement officials told The Oregonian/OregonLive in December they believe the Saudi government helped at least one of these suspects, Abdulrahman Sameer Noorah, return home before his 2017 trial in the hit-and-run death of a Portland teen. Prosecutors in Ohio allege Saudi officials helped orchestrate manslaughter suspect’s disappearance in 1988.

The Saudi Arabian Embassy in Washington, D.C., has previously said that, as a policy, the Saudi government will cover the cost of bail for any citizen jailed in the U.S. who asks for assistance. The kingdom also has denied playing any role in helping Saudi citizens escape prosecution in the U.S.

Though longtime allies, the U.S. and Saudi Arabia don’t share an extradition treaty. That makes the return of any Saudi suspect who has left the U.S. unlikely if not impossible without diplomatic or political pressure.

During a February meeting, Customs and Border Protection Commissioner Kevin McAleenan informed Wyden that his agency and others within the Trump administration had begun investigating how these suspects left.

It remains unclear to Wyden, however, what the size and scope of that investigation might look like, or if it will lead to any concrete results.

The State Department in February told him that it was unlikely to play any role in trying to secure the return of Noorah, the man accused of killing 15-year-old Fallon Smart in Portland, suggesting it would not seek diplomatic measures.

Meanwhile, the Justice Department said in a letter to the senator last month that federal law enforcement options are limited when it comes to Saudi nationals accused of crimes in the U.S. who have returned to their country.

“It is astounding that an administration so devoted to demonizing innocent refugees,” Wyden said, “is apparently unconcerned that people suspected of violent crimes were able to leave the country without consequence.”

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

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Read other stories from this series:

He was accused of killing a Portland teen. Feds believe the Saudis helped him escape

Gone: More cases emerge of Saudi students vanishing while facing Oregon charges

Saudi students who vanish before trial span states, decades

Oregon’s Merkley and Wyden seek to punish Saudi Arabia over students who vanished before trial

Oregon’s Wyden prods FBI director for answers about Saudi role in student disappearances

Not just Oregon: Saudi students in at least 8 states, Canada vanish while facing criminal charges

Feds launch investigation into disappearance of Saudi students facing U.S. charges

State Department says it won’t intervene after manslaughter suspect returns to Saudi Arabia