Two Chechens have hijacked a Russian airliner with more than 160 passengers on board soon after it took off from Istanbul.
A Turkish minister said at least one person had been injured and the plane, on a scheduled flight from Turkey, had been diverted to Cairo.
The Turkish transport minister Enis Oksuz said the hijackers were Chechens. He added they were armed with knives and one of the crew members was injured in the hijack.
The plane, a Russian built TU-154, took off at 11.30 GMT from Istanbul's Ataturk International airport. The two hijackers took over the plane 30 minutes later, the Anatolia news agency reported.
Mr Oksuz said that the aircraft was carrying 162 passengers and 12 crew members. There was also a baby aboard the aircraft. NTV television said the aircraft had left Turkish airspace. He said the airliner was flying toward Syria and that its apparent destination was an Arab country.
It is the fifth hijacking from a Turkish airport since 1998. The last was in 1999, when a hijacker armed with a knife commandeered a Cairo-bound flight shortly after takeoff from Istanbul. He surrendered to German police after the plane landed in Hamburg.
In October 1998, soldiers stormed a commandeered plane in the capital Ankara and shot a hijacker dead.
Turkish authorities have lost radio contact with the aircraft.