The infants were kidnapped from different locations in Haridwar including Har ki Pauri and the railway station on different dates, Haridwar SSP Sadanand Date said today.
Four members of the gang including a woman were arrested yesterday on a tip-off from Jwalapur Railway Station by GRP and SOG teams, he said.
Preliminary investigation has revealed that they were preparing to sell these infants to childless couples for Rs 2 to 5 lakh, he said.
The children belong to economically weaker sections from Uttar Pradesh, he said.