A pair of bombs exploded in a crowded shopping area in the southern Indian city of Hyderabad, killing at least 11 people and wounding 50 more.
It was the worst bombing in the country in more than a year, officials said.
The blasts occurred about two minutes apart at around 7 pm outside a cinema and a bus station, police said. Storefronts were shattered, motorcycles covered in debris, and food and plates from a roadside restaurant were scattered on the ground near a tangle of dead bodies. Passers-by rushed the bleeding and wounded out of the area.
"This is a dastardly attack, the guilty will not go unpunished," Prime Minister Manmohan Singh said. He appealed to the public to remain calm.
The bombs were attached to two bicycles about 150 metres (150 yards) apart in Dilsukh Nagar district, Home Minister Sushilkumar Shinde said. The district is a usually crowded shopping area near a residential neighbourhood.
Eight people died in one explosion and three in the other, Mr Shinde told reporters.