WASHINGTON — Four Saudis who participated in the 2018 killing of the Washington Post journalist Jamal Khashoggi received paramilitary training in the United States the previous year under a contract approved by the State Department, according to documents and people familiar with the arrangement.

The instruction occurred as the secret unit responsible for Mr. Khashoggi’s killing was beginning an extensive campaign of kidnapping, detention and torture of Saudi citizens ordered by Crown Prince Mohammed bin Salman, Saudi Arabia’s de facto ruler, to crush dissent inside the kingdom.

The training was provided by the Arkansas-based security company Tier 1 Group, which is owned by the private equity firm Cerberus Capital Management. The company says the training — including “safe marksmanship” and “countering an attack” — was defensive in nature and devised to better protect Saudi leaders. One person familiar with the training said it also included work in surveillance and close-quarters battle.

There is no evidence that the American officials who approved the training or Tier 1 Group executives knew that the Saudis were involved in the crackdown inside Saudi Arabia. But the fact that the government approved high-level military training for operatives who went on to carry out the grisly killing of a journalist shows how intensely intertwined the United States has become with an autocratic nation even as its agents carried out horrific human rights abuses.

It also underscores the perils of military partnerships with repressive governments and demonstrates how little oversight exists for those forces after they return home.

Such issues are likely to continue as American private military contractors increasingly look to foreign clients to shore up their business as the United States scales back overseas deployments after two decades of war.

The State Department initially granted a license for the paramilitary training of the Saudi Royal Guard to Tier 1 Group starting in 2014, during the Obama administration. The training continued during at least the first year of former President Donald J. Trump’s term.

Louis Bremer, a senior executive of Cerberus, Tier 1 Group’s parent company, confirmed his company’s role in the training last year in written answers to questions from lawmakers as part of his nomination for a top Pentagon job during the Trump administration.

The administration does not appear to have sent the document to Congress before withdrawing Mr. Bremer’s nomination; lawmakers never received answers to their questions.

In the document, which Mr. Bremer provided to The New York Times, he said that four members of the Khashoggi kill team had received Tier 1 Group training in 2017, and two of them had participated in a previous iteration of the training, which went from October 2014 until January 2015.

“The training provided was unrelated to their subsequent heinous acts,” Mr. Bremer said in his responses.

He said that a March 2019 review by Tier 1 Group “uncovered no wrongdoing by the company and confirmed that the established curriculum training was unrelated to the murder of Jamal Khashoggi.”

Mr. Bremer said that the State Department, “in collaboration with other U.S. departments and agencies,” is responsible for vetting the foreign forces trained on U.S. soil. “All foreign personnel trained by T1G are cleared by the U.S. government for entry into the United States before commencement of training.”

In a statement, Mr. Bremer said that the training was “protective in nature” and that the company conducted no further training of Saudis after December 2017.

“T1G management, the board and I stand firmly with the U.S. government, the American people and the international community in condemning the horrific murder of Jamal Khashoggi,” he said.

A 2019 column by David Ignatius of The Washington Post first reported that members of the Khashoggi kill team had received training in the United States. He wrote that the C.I.A. had “cautioned other government agencies” that some special-operations training may have been conducted by Tier 1 Group under a State Department license.

The issue was central to Mr. Bremer’s contentious confirmation hearing and the written questions from senators, asking him what role, if any, Tier 1 Group had in training Saudis who had participated in the Khashoggi operation.

A State Department spokesman declined to confirm whether it awarded licenses to Tier 1 Group for the Saudi training.

“This administration insists on responsible use of U.S. origin defense equipment and training by our allies and partners, and considers appropriate responses if violations occur,” said the spokesman, Ned Price. “Saudi Arabia faces significant threats to its territory, and we are committed to working together to help Riyadh strengthen its defenses.”

A spokesman for the Saudi Embassy in Washington did not comment.

Mr. Trump weighed installing the head of Cerberus, Stephen A. Feinberg, in a top intelligence post last year, but the appointment was never made. While the Trump administration had appointed Mr. Feinberg to lead the President’s Intelligence Advisory Board in 2018, questions emerged about potential conflicts of interest. Cerberus formerly owned the military contractor DynCorp, which among other things provides intelligence advice to the United States and other clients.

It is unclear which members of the Khashoggi kill team participated in the Tier 1 Group training. Seven members of the team belonged to an elite unit charged with protecting Prince Mohammed, according to an American intelligence report about the assassination declassified in February.

The role of operatives from the so-called Rapid Intervention Force in the Khashoggi killing helped bolster the American intelligence case that Prince Mohammed approved the operation.

“Members of the R.I.F. would not have participated” in the killing without his consent, according to the report. The group “exists to defend the crown prince” and “answers only to him,” the document said.

Members of the team that killed Mr. Khashoggi were involved in at least a dozen operations starting in 2017, according to officials who have read classified intelligence reports about the campaign.

Mr. Khashoggi, a columnist for The Post, was killed inside the Saudi Consulate in Istanbul in October 2018, his body dismembered using a bone saw. The assassination brought widespread condemnation on Prince Mohammed, who has publicly denied any knowledge of the operation.

Eight defendants were sentenced to up to two decades in prison last year, but human rights advocates criticized the punishments as aimed at lower-level agents while sparing their leaders.

The C.I.A. concluded that the prince directed the operation, but Mr. Trump said that the evidence was inconclusive and that America’s diplomatic and economic relationship with the kingdom took priority. After President Biden took office and debated the issue with his advisers before the release of the declassified intelligence report, his administration announced sanctions on Saudis involved in the killing, including members of the elite unit who protect Prince Mohammed, but chose not to directly punish the crown prince.

The earlier iteration of the training, which took place during the Obama administration, occurred before Prince Mohammed consolidated power in the kingdom. His predecessor as crown prince, Mohammed bin Nayef, was a close ally of the United States and in particular John O. Brennan, who served as C.I.A. director under President Barack Obama.

Prince bin Nayef was the Saudi counterterrorism chief and worked closely with Obama administration officials in working to dismantle Al Qaeda in the Arabian Peninsula, the terrorist group’s affiliate based in Yemen.

In 2017, Prince bin Salman pushed Prince bin Nayef from power and executed a broader campaign to wrest power from his rivals — including a notorious episode of imprisoning Saudi royals and businessmen at the Ritz-Carlton in Riyadh.

The Trump administration considered him a valuable partner in the Middle East — especially for the administration’s strategy to isolate Iran — and Prince bin Salman developed a close relationship with Jared Kushner, the president’s son-in-law who served as a senior adviser to Mr. Trump.

Prince bin Salman, the son of King Salman, is the next in line to the Saudi throne. Prince bin Nayef remains under house arrest in the kingdom.

The Tier 1 Group website lists numerous American special operations and intelligence units as clients, along with “specialty units that do not require recognition.” It said it also trains “OGA special operator teams” — one pseudonym for C.I.A. paramilitary units — as well as “international allied forces.”

Under federal rules that restrict foreign sales of American arms and military expertise, Tier 1 Group was required to apply for licenses to train the foreign operatives. Those license applications were examined by State Department officials — who were processing tens of thousands of licenses per year — and approved.

The approval would have allowed members of the Saudi Royal Guard to enter the United States on visas processed by the American Embassy in Riyadh. The path is similar to the one followed by Second Lt. Mohammed Alshamrani, a Royal Saudi Air Force officer who opened fire in 2019 at a naval air station in Pensacola, Fla., where he was receiving military flight training. The attack killed three people and wounded eight.

Tier 1 Group was founded to train U.S. military personnel, taking advantage of an expanded Pentagon budget for military personnel training in basic counterinsurgency skills, according to former American officials familiar with its operations.

One of the company’s founders, Steve Reichert, a former Marine, was working as an instructor for the security contractor then known as Blackwater when he met Mr. Feinberg. With Mr. Feinberg’s backing, Mr. Reichert set up Tier 1 Group, according to Mr. Reichert’s 2020 account of the company’s founding and former intelligence officials familiar with the efforts.

But as U.S. military training budgets began to shrink, the company, like other private security firms, began searching for new clients. By 2014, it was beginning to train foreign military units, including Saudis.

Decisions about granting licenses to American firms to train foreign nationals are usually made after getting input from numerous government agencies, said R. Clarke Cooper, the assistant secretary of state for political-military affairs during the Trump administration. The Pentagon and intelligence agencies often play a role, he said.

“These things don’t just come out of the ether,” he said.

Mr. Cooper said he could not recall any discussion about the Tier 1 Group training of Saudis, even after Mr. Khashoggi’s killing. He said there were intense deliberations inside the Trump administration about how to respond to the killing after the government concluded that Prince Mohammed most likely approved it.

In the end, he said, administration officials did not want to squander America’s relationship with the kingdom — and the strategy of isolating Iran — by taking a heavy-handed approach after Mr. Khashoggi’s death.

“No government is going to flush a significant bilateral relationship over this murder, no matter how horrific it was,” he said.

Adam Goldman contributed reporting.