Police said the 12-year-old boy died at the scene in the small town of Nossen, according to news magazine Stern.
The authorities are now hoping an autopsy might reveal other clues is still pending, news agency DDP reported.
Police have collected some statements that allege the boy was pushed in front of the oncoming bus by other students around 7:45 am, according to Stern.
“Whether they were witnesses remains unclear,” a spokesperson told news agency DDP.
Police are questioning students and witnesses who were present during the accident to determine the exact course of events that led to the death.
“We are still at the very beginning of our investigation,” a spokesperson told Stern.