Surat Police Commissioner Satish Sharma said the accused, who was arrested from Sawai Madhopur district in Rajasthan on Friday, had confessed to having killed the girl and her mother.
The officer said the accused had told them that the woman, whose body was found in Sachin area in Surat a few days before that of the minor girl in Pandesara locality, was the latter's mother.
"The man who handed over both the mother and daughter to Harshahay Gujjar demanded Rs 35,000 for them. We are investigating a possible human trafficking angle and sections related to it have been added in the case," Satish Sharma said.
The official said the girl was an eye-witness to the killing of her mother by Gujjar.
"The woman was brought to Surat after Diwali last year. She was killed as she wanted to stay with the accused but the latter opposed it as he was already married," Commissioner Sharma said, adding at least six to seven more people were involved in the crime and a police team is in Rajasthan following leads on them.
Another police team is questioning suspects in Surat itself, the police commissioner said.
The car came to the notice of the police while investigators were scouring CCTV images of Pandesara area.
Commissioner Sharma said that more CCTVs would be installed in the city as they had played a vital role in cracking this case.
"This case appeared to be a blind one as both victims were unidentified. We are working towards setting up more CCTVs in the city, especially in areas where migrant labourers stay," Commissioner Sharma said.
He said that 60 CCTV cameras would be installed in Pandesara locality, where the body of the minor girl was found, and police patrolling in the area would be intensified.
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