Russians search for plane crash clues

The plane crashed while attempting to land

Investigators are examining the wreckage of a Russian passenger plane to determine what caused it to crash.

All 145 people on board the Tupolev 154 died when it crashed on a flight from the Urals city of Yekaterinburg to Vladivostok in Russia's far east.

Shortly after search teams found one of the "black box" flight recorders, Russian Emergencies Minister Sergei Shoigu said engine failure was believed to have caused the crash.

Our specialists estimate the cause of the accident could have been a breakdown of the plane's fuel transmission system

Vladivostok Avia senior executive

He told journalists that all three of the aircraft's engines had failed and that it plummeted from a height of 800 metres.

However, he later said the accident appeared beyond explanation.

"I would not like to get into commenting on the investigation," Mr Shoigu told Russian television.

Crash theories

The AFP news agency said the minister did not rule out a defect in the plane's altimeter, a faulty manoeuvre by a crew member or even terrorist action.

The head of the Vladivostok Avia airline that was operating the plane, Vladimir Razbezhkin, told reporters at Vladivostok airport that the disaster could have resulted from an explosion caused by a leak in the fuel supply.

Relatives are making their way to the scene

No problems had been reported during take-off from Yekaterinburg.

It was carrying 136 passengers, six children and nine crew members.

Several Chinese nationals were said to be among the passengers.

Flight 352 had been approaching the city of Irkutsk for a scheduled refuelling stop.

Russia's Civil Aviation Authority said it had made two abortive attempts to land and crashed on its third approach, dropping from the sky about 30 kilometres (18 miles) away from Irkutsk and bursting into flames.

The plane disappeared from radar screens about 2110 Moscow time (1710GMT), near the village of Burdakovka.

Tu-154 crashes

1994 125 died

1994 160 died

1995 97 died

1996 141 died

Russian news agencies quoted witnesses describing a large explosion and fire in a district where many locals have dachas, or small country homes, not far from Lake Baikal.

The Kremlin press office said President Vladimir Putin ordered Prime Minister Mikhail Kasyanov to form a commission to investigate the crash.

Deputy Prime Minister Ilya Klebanov is said to be chairing the commission.

Heavily used aircraft

Russia has an elderly civil aviation fleet, mostly built in Soviet times, but has not suffered a major civilian air disaster in several years.

A Russian military plane crashed in Georgia last October, killing more than 80 people on board.

The Tu-154 is the workhorse of Russia's domestic airlines and is widely used throughout the former Soviet Union.

It is of a similar size to the Boeing 727.

Several have been involved in a number of deadly accidents in recent years.

Some aviation officials have contended that the aircraft is an unsafe plane. But others say its safety record is no worse than other heavily used aircraft.

More than 1,000 Tu-154 have been built and most remain active.