Separatist factions in Kashmir called for a two-day strike in protest. Their calls to boycott the poll in Srinagar, and the ensuing violence, resulted in voter turnout of a mere 7 percent on Sunday and forced 70 polling stations to shut down.
During clashes in Budgam district, police initially used tear gas against protesters who were throwing stones, but then opened fire, killing seven people, a senior police official told Reuters. One protester was killed in a separate incident.
Security was beefed up on Monday across the Himalayan region, with police blocking roads with barricades and restricting movement of vehicles. Some train services were also suspended in the region, a railway official said.
India accuses Pakistan of backing separatist fighters - a charge Islamabad denies. Kashmir, part of India's only Muslim-majority state, witnessed deadly protests after a well-known separatist militant was killed last year.
The violence has killed 84 civilians and wounded more than 12,000 civilians and security force personnel.
The state's chief electoral officer, Shantmanu, said "more than 200 incidents of violence" were reported on Sunday, including stone-pelting, petrol bomb attacks and setting ablaze of a polling station.
Sunday's by-election was held in the state's key city of Srinagar to fill a vacant seat in India's lower house of parliament, the Lok Sabha. A second by-election in the state is set to take place on April 12 in Anantnag.
"We are worried about Anantnag polls because it is a more sensitive area," the police official said.
On Monday, in a separate incident, Indian defense official Rajesh Kalia said four suspected militants were killed after they tried to infiltrate along the disputed frontier with Pakistan near an area known as the Keran sector.
"We noticed movement of militants early in the morning and killed them during an ambush," Kalia said. Details of the incident could not immediately be independently verified.
Each neighbor claims the region in full, but governs separate parts. Two of the three wars they have fought since independence from Britain in 1947 have been over Kashmir.
Last September, tension escalated as gunmen killed 19 Indian soldiers at an army camp in Kashmir, an attack India blamed on Pakistan-based militants.
India clamps down on Kashmir transport after poll violence kills eight
10 April 2017
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Indian police on Monday imposed curfew-like curbs on movement of people across several parts of disputed Kashmir, a day after clashes with protesters during a by-election killed eight people and injured more than 200.
