According to a tweet from Flightradar24, approximately one hour into the flight, the aircraft was in cruise flight at 29,100 feet when it abruptly lost altitude, entering a steep descent. The aircraft appeared to recover briefly at approximately 8,000 feet, then it reentered dive.
Some sources claim the sudden nose-dive was intentional because of manual crew input, but to me it sounds like the crew reacted to something extremely strange happening and tried to correct it (“let’s click the AUTO button and get some rest. Oh shit.”), especially since the aircraft “appeared to recover briefly at approx. 8,000 feet”. Sounds a lot like all the other Boeing 737-x crashes where the pilots were surprised by the sudden nosedive, wrestled manual control back, only for the systems to kick in again into a dive.
I post this not as news, but as a point of interest for me personally.