A day after the body of a 5-month-old boy was found in a water-filled drum in Kalwa in Thane district, police arrested the infant's mother and charged her with murder and disappearance of evidence, an official said.

Shrikant Shankar Chavan's kin had told police he was kidnapped on December 24 from their Mahatma Phule Nagar home, after which Kalwa police formed several teams to crack the case.