India, staging the world’s biggest election, will rerun voting at 11 polling stations in the northeastern state of Manipur on Monday after reports of violence and damage to voting machines in the state torn by months of ethnic clashes.

The election authorities declared the voting void at the 11 locations and ordered the fresh poll, the chief electoral officer of Manipur said in a statement late on Saturday.

Friday marked the start of voting by nearly one billion people in the world’s most-populous country, in an election running through June 1. Prime Minister Narendra Modi is forecast to win a rare third term on the back of issues such as growth, welfare and Hindu nationalism.

The main opposition Congress party had demanded a rerun at 47 Manipur polling stations, alleging that booths were captured and elections were rigged.

There were scattered incidents of violence on Friday in the state, including clashes among armed groups and attempts to take over polling stations under heavy security. Voters turned out in large numbers, despite the threat of clashes that have killed at least 220 people in the past year.

Manipur has been roiled by fighting between the majority Meitei and tribal Kuki-Zo people since May. It remains divided between a valley controlled by Meiteis and Kuki-dominated hills, separated by a stretch of no-man’s land monitored by federal paramilitary forces.