Kripa Shankar Singh added that 143 casualties had been admitted to hospital with injuries.
The twin blasts came without warning, according to Police Joint Commissioner Ahmed Javed.
The attacks in Mumbai, formerly known as Bombay, came minutes after Indian archaeologists claimed they found the remains of a Hindu temple below the surface of a mosque razed by Hindu zealots in 1992 in the northern city of Ayodhya.
Some media reports suggested there were actually four explosions, but no government or security body has confirmed this.
Historic monument hit
One bomb exploded near the Mumba Devi temple in the city center, the other more to the south at the Gateway of India, said Javed.
The Gateway is Mumbai's premier historic site and is usually crowded with tourists. Some of the victims were blown off the parapet by the impact.
Gateway of India packed with
tourists at this time of year
Police suspect the bombs were placed on the back seats of parked taxis, but no one has yet claimed responsibility for the attacks.
Sniffer dogs patrolled the financial sector and several tourist attractions in case more explosives had been planted in the district.
Most deaths were in the market, in a mainly Hindu area.
"There were hands and legs flying in the air, blood
everywhere," said jeweller Anil Punjabi. Bloodstained footpaths, broken glass and debris marked the sites.
The blasts were the worst in Bombay since 1993, when a
series of bombs killed at least 260 in what was seen as
retaliation for the deaths of minority Muslims after Hindu-
India's Deputy Prime Minister Lal Krishna Advani said the banned Students Islamic Movement of India (SIMI) could be behind the blasts.
"SIMI has been acting in conjunction with the Lashkar-e-Taiba and whether today's blast is also the handiwork of the same organisations will depend on the outcome of the investigation going on," he said.
But he gave no evidence for the claims. The right-wing Indian government has cracked down hard on Muslim activists in recent years, particularly those supporting Kashmiri independence, arresting SIMI"s president Shahid Badr in 2001 and banning the organisation under sweeping anti-terrorism legislation.
In the past India has also blamed similar atrocities on its neighbour Pakistan by accusing the country of harbouring Muslim extremists.
However Pakistan condemned the explosions as "act of terror".
"We deplore these attacks and we sympathise with the victims and their families," foreign ministry spokesman Masood Khan told a weekly press conference.
Meanwhile, within hours of the blasts, at least nine detonators were found on railroad tracks near the city of Nasik some 125km north of Mumbai.