Two teenage girls have been found hanging from a tree in a northern Indian village, police say, after they were gang-raped by five men in a brutal attack.

Police have arrested one man over the attack on the cousins, aged 14 and 15 and from the lowest Dalit caste, who were discovered hanging on Wednesday morning in Budaun district of Uttar Pradesh state.

A post-mortem report indicated the cousins hanged themselves late on Tuesday after being attacked, police said.

The girls had earlier walked into a field to go to the toilet because they didn’t have one in their home when they were set upon, according to local media reports on Thursday.

The attack sparked protests by the girls’ families and other villagers, who accused police of failing to act after the bodies were found.

Television footage shows the villagers including children sitting on the ground under the tree in protest with the bodies hanging above.

The families belong to the Dalit caste, previously known as “untouchables”, considered on the lowest rung of India’s deeply entrenched social hierarchy system.

Saxena said police had arrested one suspect after the girls’ relatives registered a complaint against five men for gang-rape, murder and child sexual abuse.

“A team of around 50 police officers is on the lookout for the absconding accused,” he added. Saxena could not confirm the exact ages of the attackers, but said they were in their “late teens”.

Local police officers have also been suspended from duty for their initial apathy over the crime, he said.

The attack is the latest to highlight India’s dismal record on preventing sexual violence, despite tougher laws after the fatal gang-rape of a student in New Delhi in December 2012 shook the nation’s conscience.

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