Egyptian authorities began probing the cause of a Russian passenger-plane crash in Egypt's Sinai Peninsula that killed all 224 passengers and crew on board in what may be Russia's deadliest airline disaster.

Preliminary investigations indicate the plane, an Airbus 321 operated by Russia's Metrojet, went down due to a technical problem, the state-run Ahram Gate website said, citing Egyptian security officials. The plane crashed 23 minutes after taking off from Sharm el Sheikh, a popular Red Sea resort, according to e-mailed statements from Egypt's government.

The Islamic State, in a report picked up by Al Jazeera and by the Washington D.C.-based SITE Institute, claimed responsibility in reprisal for Russian airstrikes on Syria. It's not clear that the group has weapons capable of hitting a plane at cruising altitude.

"It is technically difficult to target a plane on that level as many experts said," Egyptian Prime Minister Sherif Ismail told reporters, saying it's too early to give a reason. "We have no evidence that anything unusual was happening on the plane before it crashed."

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Russian Transportation Minister Maxim Sokolov said in televised comments that his government has "no valid information" pointing to a terrorist missile downing the plane.

The black boxes have been found, an emergency official in Sinai said. The debris from the crash is spread over an area of six to eight square kilometres (two to three square miles), Ismail said.

Bodies are being recovered from the wreckage, found in the remote Al Hassana area of central Sinai, about 50 kilometers (31 miles) south of Al-Arish, where Egyptian security forces have been waging a fierce campaign against militants in northern Sinai that have pledged allegiance to Islamic State. Workers have moved 129 bodies from the crash site, Ismail said.

Sherif Ismail, third right, examines the flight data recorder inspected by officials at the site where the plane crashed. Photo / Suliman el-Oteify, Egypt Prime Minister's Office via AP)
Sherif Ismail, third right, examines the flight data recorder inspected by officials at the site where the plane crashed. Photo / Suliman el-Oteify, Egypt Prime Minister's Office via AP)

Air France-KLM Group and Deutsche Lufthansa AG said they would avoid flying over the Sinai area until the cause of the crash is known.

In its final seconds, the plane was bucking wildly, abruptly climbing and descending before communication with the flight was lost, according to Flightradar24.com, which tracks flight routes. The plane, which took off at 5:51 a.m. Cairo time heading for St. Petersburg, had reached a cruising altitude of 31,000 feet, Egypt's Civil Aviation Ministry said in an e-mailed statement.

"We didn't receive any SOS signals from the plane," Egyptian Civil Aviation Minister Hossam Kamal told reporters.

After reaching about 31,000 feet, it leaped to 33,500 feet and then plunged back again, according to FlightRadar24. At times it dropped as fast as 6,000 feet per minute, only to reverse and climb at even higher rates, repeating the cycle several times.

As that happened, the plane was slowing to a dangerous level. About 24 seconds before losing contact, it dropped to 71 miles per hour from 470 miles, according to the data. Jetliners such as the Airbus 321 can't stay aloft at such slow speeds.

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"If FlightRadar24 data is showing a correct representation of what the aircraft was doing, then it probably rules out sabotage," said Paul Hayes, director of air safety and insurance at Ascend Worldwide. "It's probably some sort of control problem."

The pilot had sought permission to land at a nearby airport because of technical problems, Dubai-based Al Arabiya reported, citing unidentified people. The plane, which had been in service for about 18 years, was checked before it took off and no technical malfunctions were found, the state-run Middle East News Agency reported, citing Adel Mahgoub, head of the Egyptian Co. for Airports.

Metrojet isn't attributing the crash to human error, Interfax reported, citing Oksana Golovina from Tourism Holding & Consulting, which owns Kogalymavia, as the carrier is known in Russia.

Islamic State's statement doesn't specify how the group supposedly downed the plane and the local affiliate may have jumped the gun on taking credit, Mokhtar Awad, an analyst at the Center for American Progress, a research institute in Washington, said by e-mail.

Russian President Vladimir Putin declared Sunday a day of mourning, "expressing sorrow for the victims and condolences to their families and friends," the Kremlin said on its website. There have been at least 100 deadly passenger plane crashes involving aircraft operated by Russian airlines that have killed more than 2,000 since the Soviet Union collapsed in 1991, according to Aviation Safety Network data.

Egyptian President Abdel-Fattah El-Sisi ordered a swift probe to determine the cause of the crash in coordination with Russian authorities, the presidency said in an e-mailed statement.

The crash may deter visitors to Egypt, further harming the tourism industry already reeling since a 2011 uprising that pushed President Hosni Mubarak out of power, weighing on foreign-exchange earnings and contributing to a drop in the local currency. About a fifth of all tourists visiting Egypt come from Russia, making it the largest source of vacationers to the North African country.

While Egypt is leading the investigation because the crash occurred on its territory, BEA, France's air safety authority, is sending two officials to the crash site and six Airbus investigators will go as well, according to an e-mailed statement. Russia and Germany are also sending people, BEA said.

The crashed plane was produced in 1997 and was operated by Metrojet since 2012, Blagnac, France-based Airbus said in an emailed statement. The aircraft had logged around 56,000 flight hours over the course of nearly 21,000 flights. It was powered by IAE-V2500 engines.

The Airbus A320 family is by far Airbus's most popular plane type -- a single-aisle, twin-engine type typically used on shorter cross-continental routes that laid the foundation for the company's success and established it alongside Boeing Co. to create a global duopoly for large passenger planes. The A321 is the longest variant of the plane, which comes in four sizes.

--With assistance from Abdel Latif Wahba and Tarek El-Tablawy in Cairo, Alan Levin in Washington and Andrea Rothman in Toulouse.