India imposed a curfew in the capital and some areas of its restive state of Manipur on Thursday, after scores of students were injured in violence following protests against the alleged abduction and murder of two students, authorities said.

Ethnic violence has plunged the northeastern state bordering Myanmar into what many security experts describe as an intense civil war fought over land, jobs and political clout between its two largest local groups.

“Indefinite curfew had to be implemented in Imphal and in some other districts,” L Kailun, a senior police official based in the state capital, told Reuters.

More than 80 students were injured in Wednesday’s clashes, another police official said on condition of anonymity.

He added that the situation was “extremely tense” after armed mobs vandalised an office of the ruling political party and hurled petrol bombs at two police sites.

Mobile internet services have been suspended in the state for five days, officials said.

Since the violence first erupted on May 3, more than 180 people have been killed and over 50,000 have fled their homes in Manipur.

More than half the state’s population of 3.2 million belongs to the Meitei community, while the Kuki community, who make up about 43 per cent, live mostly in the hills.

Protests re-ignited over the alleged kidnapping and killing of two students of the Meitei community who had gone missing in July after their bodies were found this week. The news went viral, reviving the ethnic tension.

The state’s chief minister, N Biren Singh, who is a leader of Prime Minister Narendra Modi’s party, denounced the alleged murder and vowed maximum punishment for the culprits.

Members of the students’ families and Meitei leaders have accused Kuki militants of the latest killing, and criticised authorities for failing to end the violence.

A spokesperson for a Kuki civil society group said it did not have an immediate comment on the latest killings.

Leaders of the opposition Congress party have accused the Modi government of failing to control the violence in a state governed by his nationalist party.