A string of bomb blasts in northeastern India blamed on local rebels has killed three people and left at least nine others injured, as violence ahead of India's Independence Day is escalating. Authorities in Assam state say all of the casualties came from a powerful explosion Sunday evening in a crowded market in the town of Boko, west of the state capital, Guwahati. They say some of the wounded are in critical condition. Earlier Sunday, suspected rebels blew up two oil pipelines, causing damage but no casualties. No one has claimed responsibility for the blasts. But police suspect it was the work of militants from a separatist group known as the United Liberation Front of Asom, which has been fighting for an independent homeland since 1979.