Wearing knee-high rubber boots, workers used shovels and other hand-tools to dig through the earthen slopes in the 20-meter (65-foot) deep pit left behind by the plane. Many rectangular, mud-stained plastic containers were used to collect debris and other items.

Because of the muddy conditions encountered in the rainy Guizhou area, pumps were used to drain the water. CCTV, a state broadcaster, reported that one excavator quit working after becoming partially stuck.

There have been no survivors and the cause of the crash remains a mystery. Officials have confirmed that an air traffic controller attempted to contact the pilots multiple times after seeing the plane’s altitude fall sharply, but received no response.

On Wednesday, searchers located the cockpit voice recorder but have not yet found the flight data recorder.

Saturday’s announcement by authorities stated that the identities of 114 passengers, six crew members and 120 passengers were confirmed by forensic and criminal investigators.

The domestic flight was departing from Kunming, southwest China, at 29,000 feet (8.800 meters) when it abruptly crashed to the ground. It had just begun its descent to Guangzhou airport, which is a provincial capital and an export hub, near Hong Kong, China’s southeast coast.

China Eastern, one the four largest airlines in China, and its subsidiaries, have grounded all their 737-800 planes, totalling 223 aircraft. The carrier stated that the grounding was done as a precaution and not an indication of any problems.