A huge bomb explosion killed at least 50 people in Calcutta early today, five days after bombs killed about 300 people in Bombay in western India.
Most people were in their beds in Calcutta when the bomb exploded in the middle-class district of Bowbazaar shortly after midnight, city officials said. Two apartment buildings collapsed, trapping scores of people in the rubble, they said.
The Press Trust of India news agency reported that the death toll had risen to at least 50 by seven hours after the 12:15 a.m. blast. Firefighters continued to search for more victims.
Casualties arrived at hospitals with severed limbs and severe burns. Police said 90 to 100 people were hospitalized or treated for lesser injuries and released.
Bowbazaar is a crowded trade and residential district surrounded by Calcutta's gold market and furniture market.
Police said explosives appeared to have been stockpiled in one of the buildings and detonated because of careless handling. The explosives were to have been planted elsewhere in the city to try to spark Hindu-Muslim riots, they said.
The U.S. government issued a warning to Americans to stay away from New Delhi, India's capital, because of a "heightened threat of terrorism." Indian Interior Ministry officials said security had been beefed up in the city.
In Bombay, a U.S. forensic team began probing the origin of the plastic explosives used in the wave of bomb attacks Friday. Calcutta and Bombay, India's commercial and banking center, are on opposite coasts separated by the breadth of India.
Bombay's police chief, Amarjeet Singh Samra, said police arrested two more people believed linked to the 13 blasts in Bombay, but he declined to give details. "This is a big conspiracy with a number of cases interconnected," Samra said.
He told reporters that four people are being held and that police believe they know the identity of the mastermind. Samra refused to say who he might be or whether he is Indian.