No survivors found after China's worst air disaster in more than a decade, state media says
https://edition.cnn.com/2022/03/22/china/china-eastern-airlines-plane-crash-tuesday-intl-hnk/index.html
Unless exterior of the aircraft is heavily damaged or basic failure of mechanical parts, it's difficult to let the aircraft drop vertically.
Even if fuel runs out, the aircraft could have flied, though altitude would drop gradually.
Other possibilities are explosion inside the aircraft and hijacking.
