(CNN) -- At least five people were killed Sunday in a string of blasts before the start of a political rally in eastern India, authorities said.
The explosions occurred in Patna, in Bihar state, ahead of an appearance by opposition politician Narendra Modi, the Bharatiya Janta party's prime ministerial candidate for next year's national elections.
Along with the dead, 83 people were injured, Bihar Chief Minister Nitish Kumar confirmed. One person has been taken into custody and is being questioned, and law enforcement is developing important leads in the strikes, he said.
Kumar said there was no intelligence information before the blasts to indicate a threat. He said that next of kin of those slain will be compensated.
Authorities in Bihar have not yet determined whether the bombings were politically motivated or whether Modi himself was targeted.
But Modi has his share of detractors -- particularly in the state of Bihar, which has a significant Muslim population -- and many citizens think he could have been targeted.
Modi, who is the chief minister of Gujarat state, is a powerful but controversial Hindu nationalist leader. He has been accused of turning a blind eye to the killings of hundreds of Muslims in the wake of the burning of a train carrying Hindu pilgrims in 2002 in Gujarat.
Indian Prime Minister Manmohan Singh issued a statement condemning Sunday's blasts and called for "urgent steps to identify and take action against those responsible."
Modi, on his Facebook page, called the explosions "deeply saddening." Both he and Singh appealed for calm. The blasts did not prevent the rally from occurring. Modi made no mention of the blasts at the rally but called for peace.
Journalist Neha Sharma in New Delhi and CNN's Jessica King in Atlanta reported