At least 110 are dead after an Iranian military aircraft crashed into a 10-storey building in a densely populated district of Tehran on Tuesday.

According to reports, the C-130 transport plane crashed into the building while trying to make an emergency landing at Mehrabad international airport and exploded in a ball of fire.

All 94 passengers and crew of the plane were killed, Mayor Mohammad Bagher Ghalibaf told The Associated Press.

In addition, 21 of the building's estimated 250 residents were killed, and another 90 injured, according to Tehran state radio.

The cause of the crash is not immediately known but state media said the plane encountered a technical problem shortly after take-off from Mehrabad en route to Bandar Abbas, a port city in southern Iran.

According to a report from the British Broadcasting Corp., the city is currently blanketed in smog as the air pollution rating is particularly high, but it is not known if this played a role in the crash.

The building that was struck is in the Towhid residential complex, which is inhabited by members of the military and their families and lies in the flight path to the airport, Reuters reported.

"It is awful down here. I am suffocating," Red Crescent official Shahram Alamdari told the wire agency by telephone from the scene.

Iran has a history of airplane accidents and many of the crashes are blamed on poorly maintained planes.

In April, an Iranian airlines Boeing 707 with 157 people aboard skidded off a runway at Tehran airport and caught fire, killing three people.

In Feb. 2004, an Iranian passenger plane crashed at an airport in the United Arab Emirates, killing at least 43 people.

An Iranian Ilyushin-76 troop carrier carrying members of the elite Revolutionary Guards crashed in the south-east of the country on Feb. 2003, killing all 302 people on board.

Iran has blamed many of its air crashes on U.S. sanctions, saying they have prevented the country from repairing and replacing its aging fleet, which are believed to date back to before the 1979 Islamic revolution and the U.S. boycott of Iran.