Two black boxes from the crashed aircraft were retrieved Wednesday morning, and experts are still decoding the devices hoping to find clues leading to the cause of the accident.

The city's top official Xu Zhaojun said earlier on Wednesday that the captain had talked with air traffic controllers on the ground.

"He said he could see lights on the runway, and was ready for landing," said Xu, quoting airport authorities.

Several survivors remembered the plane touched the ground before it arrived at the airport. "I looked out and couldn't see anything -- it was pitch dark and there was no light," said Xue Xilai, a survivor who was sitting in the 10th row, close to the emergency exit.

Investigators said the plane wreckage was about 2 km from the runway.

The General Administration of Civil Aviation closed the Yichun airport shortly after the crash and no airport source was available for interview Wednesday.

Vice Minister of civil aviation Li Jian said it would take a while to publish the result of the investigation. "It's hard to make any assumption right now, but we will publish, step by step, what we can rule out."

Officials in Yichun confirmed about 18 officials from Ministry of Human Resources and Social Security and its provincial branches were also on board. They were heading for a meeting in Yichun.

A ministry official in Beijing, who refused to be named, said she knew at least two colleagues from the southwestern Sichuan Province had died and all others were injured.

Vice Minister Sun Baoshu was in critical condition. "He suffers broken bones and injures in the brain and lungs," said Dr. Li Jinchang who operated on Sun overnight.

He said the operation lasted four hours until 2 a.m.

The jet broke into two pieces before it smashed into the ground and exploded. Most of the casualties were found in the back of the cabin.

According to the death roll released by Yichun city government, the dead were aged roughly from 12 to 55, calculated from their birth dates indicated in their ID numbers.