Iranian rescuers still looking for wreckage of plane crash that killed 66 people The search continues in mountainous terrain for this weekend's plane crash.

 -- Time is ticking as Iranian rescue teams search the Zagros Mountains trying to locate the wreckage of a missing Aseman Airliner that crashed there on Sunday morning with 66 people on board.

The missing plane was an ATR 72-500 twin-engine turboprop. It left the capital city of Tehran to Yasuj, a southwestern city at 4:30 a.m. GMT on Sunday, but went off the radar 50 minutes into its journey around the city of Semirom in Isfahan Province.

Relatives of those on board have been desperately waiting all day on Sunday, but are losing hope as reports say all 66 passengers are feared dead. Those on board include 60 passengers, two flight attendants, two security guards, and the pilot and co-pilot.

According to the statement of Iran Emergency Center, the heavy winds and snow did not allow a rescue team's helicopter to approach the possible location of the crash on the first day.

The rescue operation was resumed Monday in better weather, but the plane wreckage had yet to be tracked down.

To accelerate the operation, Iran has reached out to other countries for help.

“We have asked China and European countries to immediately inform us of any image they might capture with their satellites,” Mojtaba Saradeghi, deputy head of Iran's Civil Aviation Organization, told the Iranian Student News Agency on Monday.

Family and friends have posted desperate pleas for news on the missing on social media, including one from a women who listed four co-workers killed in the accident and the statement, translated as, "Do you know we have filled your desks at the office with flowers? We shared your memories, and cried."

Russia has also sent information on the possible location of the crash to Tehran via diplomatic channels, according to Spotnik, the Russian news agency.

The Iranian airliner's fleet is very old as it has been prevented from updating for years due to severe sanctions from the West. The Islamic Republic was not allowed to purchase new Western planes and spare parts for about two decades.

In 2015, the country signed a nuclear deal with six world powers (Germany, United Kingdom, France, Russia, China and the United States), based on which Iran agreed to curb its nuclear-related activities in return for the easing of some sanctions against the country.

One of the top priorities of Iran was removing sanctions on its aviation industry. While easing these sanctions has led to a major deal between Iran and Boeing for the purchase of airplanes over the coming years, the body of the fleet of the country is still worn out.

The recent crash has led to discussions on social networks about where the West and Iranian aviation stands two years after the lifting of the sanctions on the industry.

Pouyan Tabasinejad, policy chair of the Iranian Canadian Congress, was among those to criticize Canadian Sen. Linda Frum on Twitter after she slammed Boeing for selling Iran new aircraft.

However, some of those who used to blame the West for the high number of casualties in airplane crashes in Iran are now pointing their fingers at Tehran’s mismanagement for not upgrading its fleet in the past two years after the lifting of the former restrictions.

Capt. Houshang Shahbazi became a national hero to Iranians in December 2011 after he managed to safely land a 40-year-old Boeing 727 while the gear in the nose was jammed and the front wheel did not open. He saved the life of 120 passengers on board.

Before the nuclear deal, Shahbazi was a vocal critic of the Western sanctions on Iran’s civil aviation industry. But in an interview with ABC News about the recent incident, he said time to blame the West for such incidents is over. Instead, he criticized Iranian aviation officials for not being swift enough in updating the fleet.

“It is not a humanitarian crisis. This crash is the result of a political crisis,” he said, putting the blame on where political parties choose to invest the resources of the country. “Two years has passed and managers have had enough time to buy new planes and spare parts, if it was their priority.”

However, Aseman Airliner’s technician and training manager, Capt. Bahador Ashayeri, denied any technical problem with the missing ATR plane.

“This plane was of the most modern models. ... It has no problem at all,” Ashayeri said in a live TV program on Sunday.

The weather is expected to get even colder in the Zagros Mountains on Tuesday, making the search and rescue operation more difficult.

“Regardless of the weather condition, search and rescue operation will go on,” Shahin Fathi, operation deputy of Iran’s Red Crescent Organization told the News Channel.

“However, in case of a snowfall, aerial and helicopter search will not be possible and search will go on with the rescue teams on the ground.”