Oct. 19 (UPI) -- Jamal Khashoggi, a Saudi journalist who disappeared more than two weeks ago after visiting the Saudi consulate in Istanbul, died during a fight at the facility, Riyadh announced Friday.
Saudi Arabia confirmed his death on state-run television as part of the results of a government probe. Officials said 18 people have been arrested in connection with the death, though no names have been released.
Khashoggi, a U.S. resident and Washington Post columnist, disappeared after visiting the Saudi consulate in Istanbul on Oct. 2 to get documents for his planned marriage. Security camera footage captured his entry, but not his exit, and he's not been seen since.
Trump told reporters Thursday that Khashoggi is most likely dead and Saudi officials are likely involved, but he did not explicitly put the blame on Saudi Crown Prince Mohammed bin Salman. Whoever is responsible, he said, will be punished.
"It will have to be very severe," he said. "I mean, it's bad, bad stuff."
Turkish investigators have expanded their search to include the Belgrade Forest in Istanbul, hoping to find Khashoggi's remains. Turkish officials say at least one vehicle that left the consulate is suspected to have gone to the forest, about 9 miles away.
Turkish investigators said they have audio recordings that depict a grisly scene of Khashoggi's torture, during which interrogators dismembered him.
The killing could have been retaliation for Khashoggi's writings, which often criticized the Saudi royal family.
"This one has caught the imagination of the world, unfortunately," Trump said. "It's not a positive."
Trump has not yet offered specifics on possible punishment for Saudi Arabia if leaders were found to be responsible. Earlier this week, he shied away from the idea of sanctions against the world's second largest oil producer and a key U.S. ally against terrorism in the Middle East. Trump's son-in-law and senior White House adviser Jared Kushner has strong ties to the crown prince.
CNN reported that the National Security Agency intercepted communications that contain Saudi officials discussing a plan to lure Khashoggi from his home in Virginia to Saudi Arabia, where they would detain him. The communications do not include evidence, though, that the crown prince ordered the journalist killed.
Other evidence points to Saudi intelligence officer and former diplomat Mahar Abdulaiziz Mutreb playing an important role in the case. He appears on security camera footage walking into the consulate in Istanbul with other Saudi individuals on the day Khashoggi visited. Other footage also shows him at a hotel and airport.
U.S. officials say the operation could not have happened without the crown prince knowing about it. Mutreb is part of the crown prince's inner circle and has posed with him in photographs.
Turkish officials also revealed passport scans for seven other Saudis who may have been involved in Khashoggi's disappearance -- including the head of forensic medicine at the Saudi Ministry of the Interior.
Turkish officials searched the home of Saudi consul Mohammad al-Otaibi on Wednesday. Security footage there shows Mutreb and other Saudis visited the day Khashoggi went missing.
Thursday, Trump signed off on Treasury Secretary Steven Mnuchin's decision to pull out of an investor conference in Riyadh next week. Mnuchin made the decision after meeting with U.S. Secretary of State Mike Pompeo, who just returned from Saudi Arabia and Turkey.
Mnuchin, though, said he will attend an anti-terror finance meeting with several Middle East countries hosted by Saudi officials in Riyadh later this month.