Mukesh, Sandeep and Sonu yesterday poisoned their youngest sister Preeti, then strangulated her to death and later burnt her body in a crematory here, they said.
According to the village Sarpanch Omprakash, on June 5 the girl was caught by her brothers in an objectionale position with a youth in her house due to which they got furious and killed her, police said.
A case has been registered against the three following which Mukesh and Sandeep were arrested, they said.