The victim, Mayank, hailed from Ajrawal village, police said.
Student of a private institute, Mayank was heading home after classes when the incident took place. He had boarded the bus going towards Pehowa, they said.
Damanpreet, a friend of the victim, who was travelling with him, said Mayank had an altercation with the conductor of the bus over his pass, police said.
The conductor told Mayank that his bus pass was not genuine and asked him to purchase a ticket, Damanpreet said in his statement to the police.
Also Read
Mayank's father Shiv Kumar told the police that some students told him that the conductor pushed his son out of the bus.
After the incident, the driver of the bus took Mayank to hospital at Ambala City where he was declared 'brought dead', police said.
Damanpreet's statement has been recorded and the matter was under investigation, police said.
Sadar police station SHO Ajaib Singh told reporters that a case had been registered against the conductor as well as the driver of the bus.