The accused, Anirudh Masram (24), has been arrested in this connection, they said.
According to a police complaint lodged yesterday by Doni village resident Samalvathi Bai (22), her husband Anirudh killed their eight-day-old daughter by giving her poison on Sunday, Lamta police station's in-charge inspector Vijendra Maskola said.
In her complaint, the woman stated that she smelt odour of pesticide in the room where her daughter lay dead in bed and also noticed froth from the baby's mouth, he said.
Following the complaint, the baby's body was exhumed and sent for postmortem and Anirudh was arrested yesterday, he said.
Anirudh confessed that he killed the new born as he suspected her wife's character, the police officer claimed.
The accused told the police that he had killed the baby as he suspected that she was not his child, Maskola said adding that further investigation was on in the matter.