As the girl went to the shop, the accused allegedly took the boy and fled, an official said.
A 28-year-old woman was arrested for alleged abduction of a one-and-half years old boy within 12 hours of the incident in suburban Malad, police said on Friday.
Sonam Sahu, the accused, allegedly gave Rs 200 to the boy's sister and sent her off to buy biscuits when they were playing outside their house on Thursday evening.
As the girl went to the shop, the accused allegedly took the boy and fled, an official said.
Ms Sahu was arrested on the basis of technical surveillance and the boy was reunited with his family, he added.
Further probe is on, he said.
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