A Russian passenger jet that crashed outside Moscow was intact when it hit the ground and exploded upon or after impact, the country's top investigative agency says.
In a statement on February 12, the Investigative Committee said there was no fire aboard the plane when it crashed shortly after takeoff from Domodedovo airport, killing all 71 passengers and crew.
"It has been determined that at the moment of the crash the aircraft was intact [and was] not on fire," it said. "An explosion occurred after the plane crashed."
Officials have indicated they do not believe that a terrorist act brought the plane down, but they have not announced a probable cause.
The Investigative Committee said the authorities would be considering "all theories" and examining the airline, the technical state of the Antonov An-148 aircraft, and the training history and level of experience of the pilots.
CCTV video footage of the crash that was posted on the Internet shows a ball of fire and a cloud of smoke sweeping up from a snowy field on the horizon, apparently after impact.
Searchers hunted for clues in the scattered wreckage outside the capital, one day after the plane crashed minutes after taking off on a flight to Orsk, in the Orenburg region, about 1,500 kilometers southeast of Moscow.
"The rescue effort is over. All 71 people who were on board are dead," Emergency Situations Minister Vladimir Puchkov told reporters on February 12. "My sincere condolences to their families and friends."
Tough conditions mean the emergency operation at the snow-packed site some 40 kilometers from the airport could take a week, Puchkov said.
"We are predicting rescue and recovery operations here...will continue for seven days, given the very large area where the plane debris has been scattered, heavy snow, and a tough landscape," he said.
Officials said the dead included three children, one of them a 5-year-old girl, and two foreigners -- an Azerbaijani man and a Swiss engineer whose job was connected to an oil refinery in Orsk.
The Emergency Situations Ministry said that just two bodies had been recovered by late on February 11 -- and, after a night of searching, about 200 body fragments.
There were conflicting reports about the two flight recorders -- one of which would contain a voice recording from the cockpit and the other an account of the data from the cockpit instruments.
Officials had said on February 11 that one of the recorders was recovered from the wreckage, but the Interfax news agency cited an official involved in the operation as saying that it turned out to be a piece of the plane's avionics equipment -- not a "black box."
The Investigative Committee said in its statement that the instrument data recorder had been found while searchers were still looking for the voice recorder.
There was no distress signal from the crew before the crash. The flight-tracking site Flightradar24 tweeted that the plane was descending at 1,000 meters per minute five minutes after taking off.
Officials denied reports that the pilot had reported a malfunction.
The aircraft was manufactured by the Voronezh Aircraft Production Company in 2010, the company said.
President Vladimir Putin offered his "deep condolences to all" who lost relatives, friends, and loved ones in the crash, the Kremlin said in a statement on February 11.
Putin put off a planned trip to the Black Sea resort city of Sochi on February 12 and remained in Moscow. A February 12 meeting with Palestinian Authority President Mahmud Abbas was moved from Sochi to Moscow.
The White House offered its condolences to families of the victims of the crash, saying in a statement that the United States "is deeply saddened by the tragic deaths of those on board Saratov Airlines Flight 703."
"We send our condolences to the families of those who lost their lives and to the people of Russia," the statement added.
Yelena Voronova, a spokeswoman for the airline, identified the pilot as 51-year-old Valery Gubanov, who had 5,000 hours of flight experience, and said the co-pilot, Sergei Gambaryan, was also experienced.
“The crew was experienced; the plane was reliable,” she told the U.S. television network ABC.
Speaking to RFE/RL's Russian Service, a Saratov Airlines pilot who knew Gubanov and has flown the Moscow-Orsk route many times expressed doubt that pilot error or a technical problem could have caused the crash.
"I don't believe pilot error or the theory of a technical cause," said the pilot, who declined to give his name because of the sensitivity of the situation.
The pilot said he believed the cause was a terrorist act -- an idea that the authorities have indicated is unlikely.
He said it was possible that Gubanov decided not to have the aircraft de-iced before takeoff but suggested that could not have caused the crash.
The plane had landed at Domodedovo shortly before it took off again and "simply did not have time to cool down" enough for de-icing to be needed, he said.
"Do you know how we check whether it's necessary to treat [a plane with de-icing fluid] or not?" he said. "We take a ladder, climb onto the wing, and touch it. If there's no ice, there is no need to treat it."
The Emergency Situations Ministry’s website published the official list of passengers and crew on February 11.
Most of those on board were from the Orenburg region. Psychologists were sent to the airport in Orsk to speak to anguished relatives who were there to meet their loved ones on February 11.
The Orenburg regional government declared February 12 a day of mourning in the province.
Domodedovo airport has been the focus of security concerns in the past.
In August 2004, Chechen suicide bombers destroyed two airliners that took off from the airport on the same evening, killing 90 people. A suicide bombing in the arrivals area killed 37 people in January 2011.
Russian airlines have suffered two large-scale plane crashes in recent years: A Tu-154 operated by the Russian Defense Ministry crashed into the Black Sea, killing all 92 people on board on December 25, 2016.
An onboard bomb destroyed a Russian Airbus A321 soon after taking off from the Egyptian resort of Sharm al-Sheikh, killing 224 people in October 2015. The Islamic State extremist group said it had placed the bomb aboard the plane.
The crash comes after a report by Aviation Safety Network in January that said that 2017 was the safest year in commercial aviation in history worldwide.
The report said that 10 airline accidents worldwide with 79 fatalities represented the first year with fewer than 100 deaths among records dating to 1946.