NEW DELHI, India ? A wave of bombings and shootings killed 46 people Saturday in two states in India’s remote and turbulent northeast, authorities said, underscoring the continued threat from separatist groups that have battled the government for decades.

The highest death toll was recorded in the town of Dimapur in the state of Nagaland, where near-simultaneous bombings on a crowded railroad platform and in a marketplace killed 26 people and wounded scores of others.

Meanwhile, in the state of Assam, separate bombings and shootings killed at least 20 people, including 11 who died when gunmen opened fire on a crowded marketplace in a small town near the border with Bangladesh. Police blamed the massacre on tribal guerrillas fighting for an independent homeland in Assam.

There was no indication of a link between the attacks in the two states, and no one immediately asserted responsibility for the bloodshed. But it came as a sharp reminder of the challenge posed by armed separatist groups that accuse the government of plundering the region’s natural resources while doing little to help its people.

The attack in Nagaland, on the border with Burma, was the deadliest since the main rebel group in the state agreed to a cease-fire in 1997. The state’s Naga tribe is predominantly Christian, and many members feel little connection with mostly Hindu India. Naga rebels launched India’s oldest insurgency almost half a century ago and have successfully prevented the government from opening the oil-rich region to energy development.

Within hours, neighboring Assam was rocked by a series of attacks, including the marketplace massacre and five bombings in other parts of the state. The town of Boingagoan was hit by two simultaneous explosions, one of which killed two people. Several separatist groups are fighting for an independent homeland in Assam, a hilly, forested region known for its tea plantations and mineral deposits.

In August, a powerful bomb killed at least 16 people, many of them schoolchildren, as they assembled for an Independence Day parade on the grounds of a college in Assam.

India’s interior minister, Shivraj Patil, told India’s private NDTV television that he would fly to Nagaland today to assess the situation. “The blast was very big,” he said. “For seven years, Nagaland had experienced peace. This kind of thing had not happened. We shall have to see who is involved in it.”