The victim, Raksh (24), a bus conductor by profession, was taking bath when a container truck hit the water tank, killing him on the spot, Kotwali police station Incharge, Ravendra Dwivedi said.
The mishap led to a traffic jam on the National Highway-78, as police tried to extricate the body from the site, he said.
A case has been registered in this connection, he said, adding further investigation is on.