TEHRAN: The black boxes from an Iranian airliner that crashed in flames near Tehran, killing all 168 people on board, have been found, a transport ministry official said.

"The plane's recording and flight systems have been found," Ahmad Majidi, head of the ministry's crisis unit, told the official IRNA news agency. "Our experts are examining the black boxes to try to determine the cause of the crash."

Emergency workers shift through the wreckage of a Tupolev Tu-154 passenger plane which crashed near the city of Qazvin, about 150 km (93 miles) north of Tehran, July 15, 2009. The Caspian Airlines aircraft crashed in northwestern Iran on Wednesday on its way to neighbouring Armenia and all 168 people on board were killed, Iranian media reported. [Agencies] Photo: 168 killed in Iran plane crash

The Caspian Airlines Tupolev-154 caught fire in mid-air en route to Armenia and plunged into farmland on Wednesday, killing all 153 passengers and 15 crew in the worst air disaster in sanctions-hit Iran in years.

Witnesses said the plane was ablaze before smashing into the ground and exploding near a village near the northwestern city of Qazvin shortly after take-off from Tehran.

One relief worker said at the site that all he found were "pieces of flesh and bones."

"There is not a single piece which can be identified. There is not a single finger of anybody left," he said, standing next to a body bag filled with pieces of flesh.

In Yerevan, the deputy head of the Armenian civil aviation organisation, Arsen Pogossian, said the pilot had attempted an emergency landing after an engine caught fire.

He said 147 passengers were Iranian, of whom 31 were of Armenian origin, four were Armenians and two Georgians.

Iranian officials said 10 members of the junior national judo team were also among those killed.

In Sydney, officials said an Australian brother and sister, aged in their 20s, who possibly had dual nationality, were among the dead.

Witnesses spoke of seeing the plane on fire before it plunged to earth.

"I saw the plane when it was just... above the ground. Its wheels were out and there was fire blazing from the lower parts," witness Ablolfazl Idaji told the Fars news agency.

"It seemed the pilot was trying to land and moments later the plane hit the ground and broke into pieces that were scattered far and wide."

A farmer, 18-year-old Ahmad, gave a similar account.

"I was driving my tractor when I saw a big fire in the sky," he told AFP.

"There were burnt parts scattered across the ground and I followed them and arrived at the crater. You could not believe your eyes. Nothing was left, but just a big hole with fire coming out of it."