At least 81 people were wounded on Wednesday, Prithviraj Chavan, the chief minister of the state of Maharashtra, told CNN-IBN.
"The vehicles used were scooters and motorcycles (in the attacks)," he said. Television channels also said an improvised explosive device was placed in a car, suggesting the work of local groups rather than an international terror network.
Television images showed blaring ambulances carrying away the injured at one of the attack sites. At Dadar in central Mumbai, one of the explosions left car windows shattered and uprooted electric poles.
Police were seen using sniffer digs to look for clues while local people helped paramedics carry away some of the injured.
"We heard a big blast. The building shook, the windows shattered. It was deafening," said Aagam Doshi, a witness of the blast at the Opera House and a diamond merchant in south Mumbai.
"We came outside, and the area was filled with black smoke. There were bodies lying all over the street, there was lots of blood...We saw many bodies missing arms and missing legs."
Copyright Reuters, 2011