At least 42 people have been killed in a series of blasts, minutes apart, in two locations in the southern Indian city of Hyderabad, officials say.
One blast hit a restaurant in the city
One explosion rocked an amusement park, killing at least nine people, while another blast hit a popular eating place miles away.
Some 50 people were injured in the incidents, in Andhra Pradesh state.
Andhra Pradesh chief minister, Y S Rajasekhara Reddy, described the blasts as a suspected "terrorist act".
India's Home Minister Shivraj Patil is due to visit the city on Sunday.
"To be precise, a total of five explosive devices were used," said the city's police chief Balwinder Singh.
People in the area said a huge explosion was heard in Hyderabad's Lumbini Park, popular for its restaurants and amusements, just after 1930 (1400 GMT) .
The blast happened in an open-air auditorium, which was packed with families, watching a laser light show.
Reports from the scene quoting a local police officer said at least six people in the audience were killed instantly.
One of the blasts ripped through the Lumbini amusement park
At least a dozen more, some with serious injuries, were ferried to hospital.
Another device in the auditorium failed to explode, police said.
"I saw chairs flying in the air along with bodies," Vineet, a young man who was at the show with some 200 other people, told Indian television.
"We heard the blast and people started running out past us. Many of them had blood streaming off them," PK Verghese, the security manager at the laser show, was quoted by the Associated Press news agency as saying.
"It was complete chaos. We had to remove the security barriers so people could get out."
NDTV news channel showed at least two bodies in blood-soaked clothing, slumped under seating in the park, Reuters news agency reported.
A few minutes later and several miles away, there was another explosion at a crowded local restaurant, reports said.