PATNA, India (AP) -- Authorities are investigating an outlawed Islamic group that has been blamed for ordering a series of deadly bomb blasts near an Indian opposition rally by a Hindu nationalist leader, police said Monday in a grim prelude to national elections next spring.
No group has claimed responsibility for the six small blasts, which killed seven people and wounded 83 just before the rally by Hindu nationalist opposition leader Narendra Modi.
One of two suspects arrested after the blasts told police that an outlawed Islamic group had instructed him and others to carry out the bombings Sunday as hundreds of thousands of people gathered for the rally in a central park in Bihar's state capital of Patna, police said.
"The main motive was to create panic and cause a stampede," senior Patna police official Manu Maharaj said. Officials from Modi's Bharatiya Janata Party, or BJP, said they kept news of the blasts quiet until after the rally to avoid panicking the crowd.
Modi is waging an aggressive campaign to become India's next prime minister, and critics worry his rise could exacerbate sectarian tensions between India's majority Hindus and its 138 million Muslims.
After the blasts, police detained three men in eastern Bihar state and three more in neighboring Jharkhand, where officers raided a home and seized "a huge amount of explosives" along with bomb-making materials, Maharaj said.
Police charged two of the suspects with criminal conspiracy and mass murder. The other four were released after questioning.
Authorities are investigating the possible involvement of the banned Indian Mujahideen after one of the suspects blamed the group for ordering the attack, senior Patna police official Rajesh Chandra said.
The Indian Mujahideen, which has been linked to the banned Pakistan-based Islamist rebel group Lashkar-e-Taiba, has not claimed responsibility for Sunday's blasts.
India's hardline Islamic organization Jamaat-e-Islami, meanwhile, denounced the attack and demanded swift punishment for those involved.
The death toll rose to seven Monday as several people died from their injuries. Dozens more were still being treated in a Patna hospital, including several in critical condition.
Modi offered condolences to the victims in a Twitter message after the rally.
Bihar's top elected official, Chief Minister Nitish Kumar, broke with the BJP six months ago over Modi's candidacy, which he suggested could upset communal relations within India's secular democracy of 1.2 billion people.
Modi, who has served three terms as Gujarat's leader, is credited with turning his western state into a haven for investment and industry.
But for years Modi has dodged allegations that he and his Hindu fundamentalist party colleagues looked the other way and even encouraged marauding mobs of Hindus as they killed and burned their way through Muslim neighborhoods in Gujarat in 2002, leaving more than 1,100 people dead in one of India's worst outbursts of communal violence.
No evidence directly links Modi to the violence, and he says he has no responsibility for the killings. The Supreme Court criticized his government, however, for failing to prosecute Hindu rioters who justified the rampage as revenge for a train fire that killed 60 Hindus. An independent probe in 2006 determined the fire was an accident, but a 2008 state government commission said it was planned by Muslims.
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