CBI arrested Uttar Pradesh's Irrigation Department's Junior Engineer Ram Bhawan from Banda on November 17.
Bhawan was accused of sexually abusing 50 children for a period of over 10 years.
The minors aged between 5 to 16 years.
The accused was allegedly also selling videos and photographs online using Dark Web.
Irrigation and Construction Block Engineer, Vipin Bihari Singh said, "Today we have got a letter from the CBI, the case has been filed under the POCSO Act, the suspension on the basis of the same Action is being taken since 2009, he has been detained from Chitrakoot."