Diwaker Singh, who was already married and a teacher at a primary school in Kachwa area of Mirzapur district, was involved in a relationship with Shreshtha Yadav (26) for the last two years, they said.
Yadav's marriage was recently fixed and the couple was agitated over this, a police official said.
The couple jumped in front of a freight train at the Katka railway station and committed suicide yesterday, he said, adding that the bodies have been identified by their family members.