A 45-year-old medical representative allegedly killed his 11-year-old twin daughters by slitting their throats at their apartment in Kanpur's Kidwai Nagar area.
The accused, after committing the murders, called the police himself to report the incident in the early hours of Sunday.
DCP (South) Deependra Nath Chaudhary confirmed the arrest and said no clear motive had yet emerged.
Investigations suspect depression or a psychiatric condition, with the accused reportedly growing increasingly unstable after his mother's death a few months ago.
A large quantity of medicines were recovered from the accused's room, and officials are probing whether he sedated the twins beforehand.
