For the second time in two days, small explosions rocked an Indian city, this time in Ahmedabad on Saturday evening, killing at least 29 people.
The Indian government said cities across the country had been put on alert for similar attacks.
At least 16 explosions detonated in several crowded neighborhoods in the western city of Ahmedabad in Gujarat state. the chief minister, Narendra Modi, told reporters late Saturday. Modi said 88 people were wounded.
One of the targets was a public bus, which appeared to be badly damaged, according to televised reports.
As crowded as those neighborhoods appeared, the casualties would have been far greater had more powerful explosives been used.
Law enforcement authorities did not immediately say who might have been responsible.
Indian television stations reported that they had received a statement Saturday from a group that called itself “Indian Mujahedeen” that warned of attacks. There was no way to know whether the statement was authentic or who was behind the group, which had claimed responsibility for serial blasts in Jaipur, in western India, two months ago.
On Friday, a series of similar blasts went off in the southern technology hub of Bangalore, killing one woman. The police said the explosions were intended to sow panic.
Home Minister Shivraj Patil said in a statement: “Anti-national elements have been trying to create panic among the people of our country.”
In recent years, well-planned bombings have struck several Indian cities, from an entertainment center in southern Hyderabad to crowded markets in the capital, in what officials have said were unsuccessful attempts to provoke violence between Hindus and Muslims.
Gujarat, of which Ahmedabad is the commercial center, is particularly sensitive to ethnic tensions. In 2002, a train fire that killed dozens of members of a Hindu nationalist group set off Hindu-on-Muslim violence across Gujarat, most prominently in Ahmedabad. All told, 1,000 Muslims were killed, and the state's chief minister, a firebrand Hindu nationalist politician, Narendra Modi, was accused of doing little to stop the violence.