The bodies of the sisters -- aged 7, 9 and 11 -- were found Feb. 16 in a village well in Bhandara district in Maharashtra after they had gone missing from school two days earlier, said police officer Abhinav Deshmukh. The area is more than 1,000 kilometers (630 miles) south of New Delhi, the capital.
The victims' mother said police did not take the case seriously and did nothing for several days until villagers held protests.
Deshmukh said Friday that 10 teams of 30 investigators were working on the case and that he was confident they would find the killers soon.
Police first dismissed the deaths as accidental, the Press Trust of India news agency reported. The girls' mother accused police of a shoddy investigation and said they did nothing for two days. Enraged villagers forced shops to close, burned tires and blocked a national highway passing in the area for hours earlier this week, demanding justice.
Police eventually registered a case of rape and murder after a post-mortem of the girls found that they had been sexually abused and brutally killed, PTI said.
One police officer has been suspended for not acting promptly, Indian Heavy Industries Minister Praful Patel, who represents Bhandara district in Parliament, said Thursday.
Cabinet Minister Manish Tewari called the killings a "very, very heinous assault" and said Prime Minister Manmohan Singh was sending 1 million rupees ($18,300) to the girls' family.
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The case has horrified Indians two months after they were outraged by the gang rape and killing of a young woman on a moving New Delhi bus.
The gang rape sparked nationwide protests about India's treatment of women and spurred the government to hurry through a new package of laws to protect them.
The gang rape victim and her male friend, who also was badly beaten up in the attack, were dumped naked on the roadside, and the woman died from her injuries two weeks later in a Singapore hospital. Five men are being tried on rape and murder charges in that case, while a sixth, who is underage, is in juvenile court.
A new law enacted by the government has increased the prison sentences for rape from the existing seven to 10 years to a maximum of 20 years. It also provides for the death penalty in extreme cases of rape that result in death or leave the victim in a coma.
Press; By ASHOK SHARMA]
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