The sisters' bodies were found in a village well in Maharashtra state on February 14 after they had gone missing from school, local police officer Javed Ahmed said.
The area is more than 630 miles south of New Delhi.
Enraged villagers blocked a national road passing through the area for several hours demanding justice.
The fatal gang rape of a young woman in a bus in New Delhi on December 16 set off nationwide protests about India's treatment of women. Five men are being tried on rape and murder charges.