KOLKATA — Troops patrolled the center of Kolkata, the capital of India's West Bengal state, on Wednesday a day after rival political supporters clashed during campaigning for the country's general election. With the third highest number of parliamentary seats among Indian states, West Bengal has emerged as a battleground where the BJP is attempting to make inroads to offset likely losses elsewhere and retain power. The BJP is facing stiff opposition from the Trinamool Congress (TMC), a regional party that controls the state and is one of Modi's biggest critics. More than 100 supporters of Prime Minister Narendra Modi's ruling Bharatiya Janata Party (BJP) were detained for violence in West Bengal on Tuesday, police said. The state police said no Trinamool member had been detained, but the independent election commission said it planned to investigate allegations of vandalism by party supporters. The clashes broke out as BJP president Amit Shah led a campaign procession through Kolkata, and rival party supporters threw stones and water bottles at each other. "The reason behind the violence is Trinamool Congress, not Bharatiya Janata Party," Shah told reporters on Wednesday. The TMC, led by firebrand politician Mamata Banerjee who is a contender for prime minister, blamed the violence on BJP "goons" and said it planned to hold a rally on Wednesday. Authorities said soldiers were deployed in the city to ensure there was no further violence. The seven-phase election started on April 11 and ends on May 19. The results will be announced on May 23. West Bengal has a history of election-related violence, initially between the communists who ran the state for nearly three decades and the main opposition Congress party. But now the BJP and the regional TMC have emerged as the frontrunners and clashes are erupting frequently between their supporters. "Elections matter in Bengal much more than most other states because party is the only form through which people tend to organize themselves," said Dwaipayan Bhattacharyya, a political science professor at New Delhi's Jawaharlal Nehru University. — Reuters