BEIJING — Rescue workers haven’t found any survivors from this week’s China Eastern AirlinesAuthorities said that the search for the black box continued after the crash, and they were continuing to look into it until Tuesday night.

BoeingFlying 737-800 with 132 passengers nosedived Monday afternoonIn a remote, mountainous area of Guangxi’s southern region. Officials have not confirmed the deaths or explained why this crash occurred.

Zhu Tao (director of China’s Civil Aviation Administration of China’s aviation safety office) said Tuesday that no survivors were found and that the Ministry of Public Security had closed the site.

The workforce is still in search of workers the black boxesZhu was referring to technical equipment that can be found in airplanes and could help determine the cause of the crash.

Additional challenges for search and rescue professionals include a sudden temperature drop and torrential downpour that began Tuesday evening, according to a forecast.

The crash involved an American-made aircraft. Therefore, the U.S. National Transportation Safety Board appointed a top air safety investigator for the China-led investigation.

CFM representatives will also be serving as technical advisers, according to the board. CFM, a joint venture of U.S-based companies, is General ElectricAccording to safety board, the engine engines were manufactured by Safran in France and Safran was located in France.

The nine crew members and the aircraft met flight requirements before take-off, Sun Shiying, chairman of China Eastern’s company in Yunnan province — where the flight departed from — said during Tuesday’s press conference.

China Eastern Airlines shares gained slightly Wednesday morning in Hong Kong. Boeing shares gained 2.8% overnight.