NEW DELHI (AP) — Angry villagers in western India threatened Saturday to resume a highway blockade unless police show progress in the search for suspects in the rape and killing of three young sisters.

The girls’ bodies were found Feb. 16 in a village well in Bhandara district of Maharashtra state after they had gone missing from school two days earlier. According to news reports, their mother has said the girls were 6, 9 and 10 years old.

The mother said police did not immediately take the case seriously and did nothing until villagers held protests this past week, including blocking the highway. On Saturday, they threatened to block it again if police do not show progress in their investigation.

Police officer Abhinav 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.

On Saturday, a senior police official investigating the case said that some men were being questioned about the rape and killing of the girls, but that no arrests had been made. The official spoke on condition of anonymity because he was not authorized to speak to the media.

The headmaster of the girls’ school was suspended Saturday for failing to inform the family or police that the girls were missing, CNN-IBN television channel reported. Teachers and students had reported to the headmaster that the three girls were not present during lunch on Feb. 14, the report said.

Hundreds of people, including schoolchildren, protested in Bhandara on Saturday, demanding greater safety for women and girls. They shouted slogans against police and district authorities, accusing them of failing to curb crimes against women.

The case has sent shock waves across India, coming just two months after a fatal gang rape of a young woman on a moving bus in New Delhi. The New Delhi incident sparked nationwide protests about India’s treatment of women and spurred the government to hurry through a new package of laws to protect them.

A new law enacted by the government increases 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.