TEHRAN: An Iranian passenger plane crashed Wednesday in northwest Iran, killing all 168 people on board, state media reported.

This image made from television broadcast by Iran's Press TV, Wednesday, July 15, 2009, shows they say wreckage from a crashed Iranain passenger plane, a Russian-made Caspian Airlines jet that crashed Wednesday in northwest Iran, killing all 168 people on board, state media reported. [Agencies]

Footage from the scene on state-run Press TV showed a deep trench smashed into an agricultural field by the impact, littered with smoking wreckage. It showed a large chunk of a wing, but much of the wreckage appeared to be in small pieces.

The Qazvin emergency services director Hossein Bahzadpour told the IRNA news agency that the plane was completely destroyed and shattered to pieces, and the wreckage was in flames. "It his highly likely that all the passengers on the flight were killed," Bahzadpour said.

He did not give a number, but Iranian Civil Aviation Organization spokesman Reza Jafarzadeh told state television that 153 passengers and 15 crewmembers were on board. State TV said all were killed.

A Caspian Airlines representative told AP in Yerevan that most of the passengers were Armenians, and that some Georgian citizens and other nationalities were on board. The representative spoke on condition of anonymity because she was not authorized to talk to the press.

Caspian Airlines is a Russian-Iranian joint venture founded in 1993. Iran has frequent plane crashes often because of bad maintenance of its aging aircraft. Tehran blames the problem in part on US sanctions that prevent Iran from getting spare parts for some planes. Caspian Airlines, however, uses Russian-made Tupolevs whose maintenance would be less impaired by American sanctions.

In February 2006, a Russian-made TU-154 operated by Iran Airtour, which is affiliated with Iran's national carrier, crashed during landing in Tehran, killing 29 of the 148 people on board. Another Airtour Tupolev crashed in 2002 in the mountains of western Iran, killing all 199 on board.

The crashes have also affected Iran's military. In December 2005, 115 people were killed when a US-made C-130 plane, crashed into a 10-story building near Tehran's Mehrabad airport. In Nov. 2007, a Russian-made Iranian military plane crashed shortly after takeoff killing 36 members of the elite Revolutionary Guards.