Russia stoked suspicions today that a rocket, misfired during a Ukrainian military exercise, downed a passenger jet over the Black Sea with the loss of up to 78 lives.
As investigators said some of the debris at the crash site could not have come from the doomed aircraft, Defence Minister Mr Sergei Ivanov said he had asked Ukraine for information on a specific missile fired on the day of the disaster.
"I have sent an urgent request to my Ukrainian colleague (Defence Minister) Oleksander Kuzmuk for more technical information on the launch of a S200 missile which was fired on October 4 at 1341 Moscow time (0941 GMT)," Mr Ivanov told Russia's RTR television channel.
Ukrainian forces were carrying out live-missile firing exercises on the Crimean Black Sea peninsula on Thursday when the Sibir airlines TU-154 jet exploded and crashed into the sea around 200 km (125 miles) away.
Ukraine's military denied its forces had shot down the airliner, bound for Novosibirsk in Siberia from Tel Aviv, saying the plane had been out of range of the exercises.
But a day later, Ukrainian Prime Minister Anatoly Kinakh appeared to retreat from those denials, saying the missile theory had a right to exist .
Washington has said a US spy satellite detected the rocket plume of a missile close to the crash area, and discounted the possibility the tragedy was an act of terrorism, one of the first theories touted for the crash.