The US has expressed concern over reports of a video that showed two women being paraded naked in the north-eastern Indian state of Manipur.
The assault on the women took place almost three months ago but became public last week after the video went viral, sparking global outrage.
A US spokesperson called the incident “brutal” and “terrible”, Reuters reported.
India is yet to comment on the statement.
But earlier this month, the Indian government had responded sharply after a US official said that his country was “ready to assist” in resolving the crisis in Manipur.
Foreign ministry spokesperson Arindam Bagchi said that he had not seen the comments, made by US ambassador Eric Garcetti, personally but that foreign diplomats usually did not comment on India’s “internal developments”.
Tensions have escalated in Manipur where ethnic clashes between the majority Meitei group and the tribal Kuki minority have killed more than 130 people and displaced nearly 60,000 since May.
The video, which was first circulated on Thursday, shows two Kuki women being pushed around and groped by a mob from a village dominated by Meiteis.
It sparked widespread outrage and condemnation, leading to the arrest of six men. According to a police complaint, one of the women was gang raped. The complaint added that a third woman was also forced to strip but she is not seen in the video.
Questions are being raised about why it took police so long to act – the complaint had been lodged just days after the incident and many of the men are clearly identifiable in the footage.
Last week, opposition lawmakers disrupted parliament’s monsoon session in capital Delhi, demanding a debate on the situation in Manipur.
They have also demanded that Prime Minister Narendra Modi address the issue in parliament – and are set to hold a protest outside the parliament on Monday over this.
After the video went viral, Mr Modi condemned the assault as “shameful” and promised tough action.
Protests have also erupted in Manipur, where thousands gathered over the weekend demanding the arrest of men involved in the assault.
There have also been reports of Meities living in the neighbouring Mizoram state leaving for Manipur and Assam state after an organisation of former insurgents issued a “warning” about their safety.
However, the Mizoram government has assured the Meitei community of their security in the state.
On Sunday, the organisation also clarified that its statement was not a warning, but an “advisory requesting Meities living in Mizoram to exercise caution in the light of the public sentiments”.
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