The incident took place yesterday night when Gopal shot his wife Sunita killing her on the spot, they said.
The body was found on bed with bullet injuries on her abdominal area.
The brother of the deceased, Brijesh, lodged an FIR against Gopal, police said, adding that the accused is absconding.
Police said that Sunita, a mother of two, was the second wife to Gopal, who served as a part time instructor at a junior high school.
The accused's motive behind the murder is still unknown and the matter is being probed, police said.