Questions about what happened to Metrojet Flight 9268 continue to mount as details about what was discovered on the plane’s cockpit voice recorder have surfaced.

Theories as to what happened to cause the plane carrying 224 people from Sharm el-Sheikh in Egypt to St. Petersburg in Russia to crash Saturday range from mechanical  failure to a terrorist bomb.

The one thing known for sure Tuesday is that 23 minutes into the flight, at a cruising altitude of 31,000 feet, something catastrophic happened to Flight 9268 over the Sinai Peninsula.

Here’s what we know today

The latest

  • Cockpit recordings reveal  "sounds uncharacteristic of routine flight," according to a report from the Interfax news agency. Interfax quoted officials in Cairo who say they have heard audio recordings from the Airbus 321's cockpit voice recorders. Interfax reports the pilot spoke to air traffic controllers four minutes before the aircraft disappeared from radar. The transcript indicated that the conversation was routine until the "sounds uncharacteristic of routine flight" were heard. The source of the quote about the transcript was not named.

What we found out since Saturday:

  • According to U.S. intelligence sources, a heat flash was detected by a U.S. infrared satellite at the time the passenger jet broke apart over the Sinai Peninsula. According to one report, the U.S. intelligence community believes the heat flash indicates an explosion occurred on the plane, causing it to crash. The Pentagon told ABC News that the heat flash could also have been recorded from some military activity in the area that had nothing to do with the plane crash.
  • The Russian news agency Tass reported that "elements that were not part of the plane" were found at the crash site," and  that those elements had been "sent for analysis."
  • The plane is believed  to have broken in two while flying at 31,000 feet. Debris from the plane was scattered over an area 8 miles long and 4 miles wide, indicating the plane came apart at a high altitude.
  • According to the Associated  Press, Alexander Smirnov, deputy general director of the airline, Kogalymavia (the legally incorporated name of Metrojet) said Monday, "We rule out a technical fault of the plane or a pilot error. The only possible explanation could be an external impact on the airplane.
  • The airplane suffered some damage four  years ago when the tail section hit the tarmac on a landing. According to Kogalymavia's engineering director, the plane was fully repaired after the accident.
  • The Airbus A321 was owned by the Irish firm Willmington Trust SP Services (Dublin) Ltd and leased to Metrojet.
  • U.S. Director of National Intelligence James Clapper said Monday he knew of no "direct evidence" that terrorism was to blame for the crash, but that he "wouldn't rule it out." "We don't have any direct evidence of a terrorist element yet," he said.
  • Claims made by Islamic militants that they shot down the plane have been dismissed by most aviation and military authorities. It is not believed that ISIL has the technical  capability to take down a plane at the cruising altitude of more than 30,000 feet.
  • Flightradar24 reports that the plane experienced sharp changes in altitude and increased its speed dramatically just before it disappeared from radar.  Flightradar24 is a website that tracks planes around the world.
  • Whatever  happened happened quickly because the crew did not have time to send a distress signal according to Egypt's civil aviation minister and Russian officials.  There were early reports  that  the  plane's captain may have tried  to make an emergency call about a technical issue, but those  reports have not  been confirmed.
  • The plane was built  in 1997. Metrojet had been using the plane since 2012, according to Airbus, the plane's maker. The plane had 56,000 flight hours.
  • Two hundred-seventeen passengers were aboard the flight -- 209 Russians, four Ukrainians and one from Belarus. Where the three other passengers were from was not disclosed. There were seven crewmembers on Flight 9268.
  • Bodies recovered so far from the crash site are said to be  mostly intact with no signs of major burn injuries.

Sources: The Guardian, The Independent, CNN, The Associated Press, The BBC, Interfax News