According to Egypt’s security forces, as cited by Reuters, a technical fault was to blame for the crash.
Search and rescue teams are finding bodies in a radius of up to 5km (3.1 miles) from the crash site. Approximately 150, some burnt, have been pulled out of the wreckage so far.
The sources say the aircraft took almost a vertical trajectory as it plummeted down. Large parts of the fuselage burned in the process.
Vertical descent and burning prior to impact are concerning...
If they are finding bodies (and other crash debris?) more than 3 miles from the crash site, I would say that indicates that the aircraft broke up at altitude.