The cause of the crash was not known, but two major European airlines announced they would stop flying over the area for safety reasons after a local affiliate of the extremist Islamic State group claimed it "brought down" the aircraft. Russia's transport minister dismissed that claim as not credible.
Almost everyone on board the Airbus-A321-200 operated by the Moscow-based Metrojet airline was Russian; Ukraine said four of its citizens were passengers. Russian officials did not give a specific breakdown of the 217 passengers' ages and genders, but said 25 were children. There were seven crew members.
A civil aviation ministry statement said the plane's wreckage was found in the Hassana area some 70 kilometers (44 miles) south of the city of el-Arish, in the general area of northern Sinai where Egyptian security forces have for years battled local Islamic militants who in recent months claimed allegiance to the Islamic State group.
The ministry said the plane took off from the resort city of Sharm el-Sheikh shortly before 6 a.m. for St. Petersburg in Russia and disappeared from radar screens 23 minutes after takeoff. Egyptian Prime Minister Sherif Ismail toured the crash site and later told a Cairo news conference that 129 bodies had been recovered.
Photos from the site released by his office showed the badly damaged sky blue tail of the aircraft, with the Metrojet logo still visible. In the background, heaps of smoldering debris dotted the barren terrain.
One photo showed a member of the search team holding the flight recorder, or black box, which Ismail said would be scrutinized as investigators try to determine what caused the crash. Russian investigators were expected to arrive in Egypt on Sunday.
Natalya Trukhacheva, identified as the wife of co-pilot Sergei Trukachev, said in an interview with Russian state-controlled NTV that her husband had complained about the plane's condition.
She said a daughter "called him up before he flew out. He complained before the flight that the technical condition of the aircraft left much to be desired."
One Egyptian official, Ayman al-Muqadem of the government's Aviation Incidents Committee, said that before the plane lost contact with air traffic controllers, the pilot had radioed and said the aircraft was experiencing technical problems and that he intended to try and land at the nearest airport.
It was impossible to independently confirm whether technical problems were to blame, and no other Egyptian official repeated the claim on Saturday.
In a statement on its website, Metrojet said the A321-200 aircraft was in good shape and that the pilot was experienced. It identified the captain as Valery Nemov and said he had 12,000 hours of flying experience, including 3,860 in A321s.
Russian Transport Minister Maxim Sokolov said officials from Moscow and Cairo were in touch over the incident. The Egyptian officials, he said, had not confirmed the claim by Islamic State militants who said they "brought down a Russian plane over Sinai state with more than 220 Russian crusaders on board." The militant group did not provide any evidence to back up its claim.
"Based on our contacts with the Egyptian side, the information that the airplane was shot down must not be considered reliable," Sokolov said, according to a report by the Interfax news agency.
An English-language statement issued by the office of Egyptian President Abdel-Fattah el-Sissi spoke of Russian leader Vladimir Putin commending the efforts made by authorities in Egypt "to uncover the circumstances surrounding the incident."
Militants in northern Sinai have not to date shot down commercial airliners or fighter jets. There have been media reports that they have acquired Russian shoulder-fired, anti-aircraft missiles. But these types of missiles can only be effective against low-flying aircraft or helicopters. The Russian airliner was cruising at 31,000 feet when it lost contact with air traffic controllers, according to Egyptian aviation officials.
In January 2014, Sinai-based militants claimed to have shot down a military helicopter; Egyptian officials at the time acknowledged the helicopter had crashed, but gave no reason.
But two major European airlines - Germany's Lufthansa and Air France - were not taking any chances. Both announced Saturday they would immediately stop flying over Egypt's Sinai Peninsula for safety reasons until the cause of the crash was determined. Their aircraft would take alternate routes to reach destinations in the region.
Spokeswomen for the airlines spoke anonymously in line with their respective companies' regulations.
Egypt's foreign minister, Sameh Shukri, warned "foreign" countries that he did not identify against taking measures that reflect speculations on the cause of the crash. "That will impact the Egyptian economy and lead to damages. These nations must consider this as well as their relations with Egypt," he said.
Friends and relatives of the crash victims were gathering Saturday at a hotel near St. Petersburg's Pulkovo airport. Psychologists were meeting with them in a large conference room off the lobby and police kept journalists away. Some left the room occasionally, looking drawn with tear-stained faces.
Yulia Zaitseva was one of them. She said her friends, newlyweds Elena Rodina and Alexander Krotov, were on the flight. Both were 33. Zaitseva said Rodina, her friend for 20 years, "really wanted to go to Egypt, though I told her, 'Why the hell do you want to go to Egypt?'"
"She was a very good friend who was ready to give everything to other people. To lose such a friend is like having your hand cut off," Zaitseva said, adding that Rodina's parents feel "like their lives are over."
Russian airlines became infamous for poor safety in the early years following the 1991 collapse of the Soviet Union, which caused severe financial troubles and regulatory disorder. Although accidents have diminished in recent years, crashes persist, many of them blamed on human error.
According to Russian news agencies, the flight was chartered by the St. Petersburg-based Brisco tour company. The plane was made in 1997 and has since 2012 been operated by Metrojet.
Officers from Russia's top investigative body raided the offices of Metrojet and Brisco on Saturday, searching the premises and questioning employees. Investigative Committee spokesman Vladimir Markin said agents also took samples of fuel from the airport in the Russian city of Samara where the plane stopped Friday before heading to Sharm el-Sheikh, where it had overnighted.
Roughly three million Russian tourists, or nearly a third of all visitors in 2014, come to Egypt every year, mostly to Red Sea resorts in Sinai or in mainland Egypt.
"It is too premature to detect the impact this will have on tourism. We need to know what happened first," Tourism Ministry spokeswoman Rasha Azazi told The Associated Press.
There was no sign of anything unusual at Sharm el-Sheikh's airport just hours after news of the disaster broke. Hundreds of vacationers, mostly from Europe and the Middle East, were arriving and departing. Flights in the afternoon were leaving at the rate of four to five per hour, with lines for international check-in spilling out the main gates.
Pavel Moroz, a 30-year-old engineer from Moscow, arrived in Sharm el-Sheikh on Saturday afternoon on a Metrojet flight. He plans to stay for a week to take a scuba diving course.
"We heard the news a few hours before leaving and thought for a bit about canceling our trip, but then decided to go anyway and everything was fine," he said as he left the airport.