Kiev accepts jet crash missile theory

Kuchma reported to have turned down defence minister's offer to quit

KIEV, Ukraine -- Ukraine has accepted for the first time that one of its missiles may have shot down a Russian passenger plane, reports say.

Ukraine initially denied any responsibility for the tragedy in which 78 people, mostly Israelis travelling from Tel Aviv to Siberia, died last week.

But the chief of the Ukrainian Security Council, who is also a member of the commission investigating the crash, accepted on Friday that it was possible that a missile fired during military exercises had hit the plane over the Black Sea, Interfax news agency reported.

Yevhen Marchuk told reporters: "The reason for the crash could be an unintentional hit by an S-200 missile during the Ukrainian air defence exercises."

CNN has not yet independently confirmed the Russian news agency reports.

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Vladimir Rushailo, head of the investigatory commission, told reporters in the southern Russian city of Sochi went further -- telling reporters that the plane had been hit by a missile, Interfax reported.

"The Tu-154 flying from Tel Aviv to Novosibirsk crashed because it was hit by the warhead of an anti-aircraft missile," Rushailo said, adding that investigators were continuing to examine fragments of the downed plane.

An explosion had been seen by a plane flying near the Sibir jet and early fears were that it could have been the result of an act of terrorism.

But U.S. officials said that the crash had been caused by an S-200 missile fired mistakenly by Ukrainian forces during military exercises on the Crimean Peninsula.

Pressure has been mounting on Ukraine's leadership to take responsibility for the crash.

Ukrainian military officials had so far heatedly denied they were at fault, but Ukrainian President Leonid Kuchma said on Thursday that defence minister Oleksandr Kuzmuk had submitted his resignation immediately after the tragedy. The resignation was rejected.