Saudi Arabia’s explanation of why its agents had strangled the dissident journalist Jamal Khashoggi in the kingdom’s consulate in Istanbul was met with a flood of international skepticism on Saturday, even as President Trump said this new account that he was killed after a fistfight sounded credible.
A Saudi official offered the kingdom’s first explanation for the involvement of a doctor of forensic medicine specializing in autopsies — a critical detail adding to international doubts about the kingdom’s story. The doctor was dispatched to help clean up fingerprints or other evidence if necessary, the official said, not to help dismember Mr. Khashoggi’s body in order to dispose of it after a premeditated assassination, as Turkish officials have charged.
The Saudis appeared to have bet heavily that they can persuade the world that Mr. Khashoggi, a bespectacled 60-year-old writer, was strangled only after he had engaged in a fistfight with a team of Saudi agents at the Saudi Consulate in Istanbul.
In their latest version of events, they insisted that the agents had flown to Istanbul to carry out a mission without any specific authorization or even the knowledge of the crown prince, Mohammed bin Salman, 33, the kingdom’s de facto ruler.
The credibility of the new account could determine the continued willingness of Western powers to work closely with Prince Mohammed, who has seized power in the kingdom more tightly than any ruler in at least half a century. The Trump administration has embraced him as the central pillar of its Middle East strategy — from containing Iranian influence to reaching a peace deal between Israel and the Palestinians.
The new Saudi explanation of Mr. Khashoggi’s disappearance emerged only after more than two weeks of officials’ insisting that Mr. Khashoggi had left the consulate.
The killing of Mr. Khashoggi, a resident of Virginia and a Washington Post columnist who left Saudi Arabia last year for voluntary exile, has spurred an extraordinary international backlash against the kingdom and the crown prince. The storm of recrimination has far exceeded the public criticism the crown prince previously received for the kidnapping of the Lebanese prime minister or for leading a catastrophic war in Yemen.
But King Salman on Saturday only reinforced his support for the crown prince, his favorite son, putting him in change of an overhaul of Saudi intelligence services in response to the scandal.
Mr. Trump said that he was willing to accept the new Saudi account even as lawmakers in both American political parties expressed grave doubts. They noted that the Saudi narrative was inconsistent with the conclusions of United States intelligence agencies and that the Saudis — including the crown prince — had depleted their credibility by maintaining for weeks that Mr. Khashoggi had left the consulate.
On Saturday, President Recep Tayyip Erdogan signaled that he, too, would reject the Saudi explanation.
“We will not allow things to remain covered,” Omer Celik, a spokesman for Mr. Erdogan’s governing Justice and Development Party, said in a report by the semiofficial Anadolu news agency.
“We will use all the opportunities that we have to reveal what happened, and this is the intention of our president.”
Turkish officials have said they have audio recordings and other evidence that could discredit the new Saudi account by showing that the team intended from the start to assassinate and dismember Mr. Khashoggi.
A key part of that evidence, the Turks say, is the presence of the doctor specializing in autopsies, Salah al-Tubaigy, who they say moved quickly and matter-of-factly to cut up the body. He even suggested to the agents working with him that they listen to music as he did while they carried out the gruesome work, according to Turkey’s account.
A Turkish official familiar with the investigation has said that Dr. Tubaigy dismembered the body with a bone saw — a standard instrument used in autopsies — that he had brought for that purpose.
Turkish officials, however, have described that evidence only on the condition of anonymity. The authorities have declined to share the recordings or other evidence with the public or even with American intelligence agencies, with whom they often work closely.
That reticence has raised questions about their ability to back up their statements, and skeptics have suggested that Mr. Erdogan may seek to avoid a full diplomatic rupture by reaching some accommodation with Saudi Arabia, an important regional power that has been both an ally and a rival to Turkey at times.
The senior Saudi official, who spoke on the condition of anonymity because the kingdom’s investigation was continuing, said the doctor “was added to the team as a forensic expert.”
“In case the team’s presence was revealed and the operation was compromised,” the official said, Dr. Tubaigy was expected to remove incriminating evidence like fingerprints.
The official denied that the doctor brought a bone saw, as Turkish official have said. The Saudi official offered no explanation for why the doctor was a specialist in autopsies rather than, say, in fingerprints or other evidence.
On Saturday, the director of the Turkish Arab Media Association — who is close to Mr. Erdogan and had been a friend Mr. Khashoggi’s — described the Saudi account as “far from reality.”
The director, Turan Kislakci, called for a full accounting of the killing and urged the removal of the Saudi crown prince from power.
“This is not over. It’s just starting,” he said. “We want Jamal’s murderers to be punished,” he added, including “the authority that gave the orders.”
Mr. Kislakci also demanded that the Saudis reveal the location of Mr. Khashoggi’s remains.
“Give Jamal back to us,” he said. “Give him back so we can raise his funeral.”
Amid the skepticism, the Saudi government has sought to convey the impression of business as usual.
The Foreign Ministry tweeted a large photo of Prince Mohammed as the head of a high-level committee formed by the king to restructure the Saudi intelligence agency in the aftermath of Mr. Khashoggi’s killing. The kingdom’s allies around the region — including Egypt and most of the Persian Gulf monarchs — expressed strong support for Saudi Arabia’s self-investigation.
Saudi officials, meanwhile, sought to distance Prince Mohammed from any responsibility for the killing even as they singled out one of his closest advisers as the culprit, Gen. Ahmed al-Assiri, the deputy chief of intelligence.
The Saudi official said on Saturday that the kingdom’s intelligence agency had issued only a general order to retrieve dissidents in exile like Mr. Khashoggi, but had not specified the means to do so. The Saudis’ internal investigation, the official said, had concluded that General Assiri, on his own, had put together a plan to bring back Mr. Khashoggi.
But although the crown prince had not explicitly ordered an abduction or assassination, the official asserted, “as the order went down the chain of command, the vagueness and aggressiveness increased,” and General Assiri and the team might have interpreted “return him to the kingdom” as instructions to kidnap Mr. Khashoggi.
It was not immediately clear how the planners of the mission obtained the use of two private charter jets from a company close to the crown prince and the Interior Ministry. But the Saudi official acknowledged that 15 Saudis arrived in Istanbul on Oct. 2 — the day Mr. Khashoggi disappeared inside the consulate — as the Turks have said.
The official said that the leaks from Turkish authorities had misidentified some of the 15 because of the spellings of their names or other details, but he did not disclose how many people were supposedly misidentified.
One member of the team, Gen. Maher Mutreb, was selected for the mission specifically because he knew Mr. Khashoggi. General Mutreb, an intelligence officer, had worked with Mr. Khashoggi when both were stationed in the Saudi Embassy in London years ago, this person said.
The participation of General Mutreb, however, may also undercut the Saudi assertions that Prince Mohammed was unaware of the plan. An investigation by The New York Times revealed that General Mutreb has frequently traveled with the crown prince in his entourage. At least three other Saudis named as suspects by the Turks appear to have links to the crown prince as well.
The Saudi official said the 15 agents had been divided into three teams: one for logistical support and transportation; one for counter-surveillance and operational security; and another for the execution of the operation. Another general in addition to General Mutreb was part of the team.
The official said that the team had initially sought to persuade Mr. Khashoggi to return home.
“He didn’t want to have the discussion, so more or less he tried to leave the room,” the official said.
The agents tried to stop him. An altercation ensued. Mr. Khashoggi started screaming, and one of the agents put him in a chokehold.
“That is how he died,” the official said. “It didn’t last that long.”
The official offered no explanation for why Mr. Khashoggi would try to resist when he was overpowered. The official also said that the Saudi authorities do not yet know what the agents did with the body.
“They say they gave it to one of their local collaborators to dispose of,” the official said, though he declined to disclose whether that “collaborator” was Saudi, Turkish or of another nationality.
The Saudis have announced 18 arrests in connection with the investigation, and the official said those arrests included the 15-member team, two consular workers and a driver. General Assiri was not among those arrested, raising questions about what consequences he might face.
The official said the team had sought to hide Mr. Khashoggi’s killing from the crown prince. The crown prince began asking questions after details appeared in the Turkish media, the official said. But he offered no explanation for why it took two weeks before answers emerged.