Feb. 12 (UPI) -- Bad weather, human error and poor aircraft maintenance are viewed as potential causes for a plane crash in Russia that killed 71 people, investigators said.
A Saratov Airlines jet, an Antonov An-148, crashed Sunday four minutes after it departed Moscow's Domodedovo airport. It was headed to Orsk, 900 miles away.
All 65 passengers and six crew members aboard the plane died.
Russian President Vladimir Putin offered condolences and ordered an investigation.
By Monday morning, members of Russia's Emergency Ministry arrived in Orsk to obtain DNA samples from relatives of those aboard the flight. Grief counselors also arrived in Moscow and in Orsk after the ministry received over 700 requests for psychological aid.
An engine failure was the likely cause of the crash, the Russian-language business newspaper Kommersant reported. Security video suggests an explosion occurred after takeoff, followed by a ball of fire as the plane rose and then fell in the sky. This conflicts with an initial statement by the Russian government's Investigative Committee, which said the explosion occurred after the aircraft crashed.
A parametric recorder and voice recorder were recovered at the site of the crash, Russian news agency Interfax reported.
Ukraine, the "state developer of the aircraft," will be involved in the investigation.
By 1 p.m. Monday, nearly 1,000 people involved in a search operation in the village of Stepanovskoye, near Moscow, found 300 fragments of the plane and more than 200 human fragments, the emergency ministry said.
Saratov Airlines grounded its fleet of six An-148 planes after the crash.