The death toll from yesterday’s wave of bombings in the Indian city of Ahmedabad has risen to 45, a government official said today.

Jaynarayan Vyas said 161 people were injured when 16 separate small bombs went off in several parts of the city, which has a history of violent clashes between the Hindu majority and Muslim minority. He also said that 30 people had been arrested in connection with the explosions, which came a day after seven synchronised explosions rocked the southern city of Bangalore, the hub of India’s burgeoning information technology industry, killing two and wounding five others.

Yesterday’s attacks in Ahmedabad happened in two waves early in the evening local time. Some of the devices were hidden in lunchboxes or bicycles. The first series exploded near busy market places. The second, about 20 minutes later, went off in and around a hospital where casualties were being taken. At least six people died there.

‘We saw a blue bag near the trauma centre, and before we could react we saw it explode in a shine of blinding light, and some 40 people were hit by flying shrapnel,’ said Vipul Patil, a doctor at the Dhanwantari hospital.

The side of a bus was blown off and its windows shattered while another vehicle was engulfed in flames.

Prithviraj Chavan, a junior in the prime minister’s office, called yesterday’s bombings "deplorable" and said they were set off by people "bent upon creating a communal divide in the country". That is the sort of language officials tend to use when blaming Islamic militants suspected of being behind a series of coordinated bomb attacks across the country in recent years. Targets have included mosques, Hindu temples and trains.

‘Anti-national elements have been trying to create panic among the people of our country. [The] blasts in Ahmadebad seem to be part of the same strategy,’ the federal home minister, Shivraj Patil, said.

Several television stations said they had received an email claiming responsibility from a group called the Indian Mujahideen at the time of yesterday’s blasts. The same group said it was behind bombs in Jaipur, western India, in May that killed more than 60 people. The email made no mention of Friday’s bombings in Bangalore, according to reports.

Narendra Modi, the chief minister of Gujarat state, which includes Ahmedabad, condemned the blasts as "a crime against humanity" and said the group or groups behind them were "using a similar modus operandi all over the country". The state government home Minister Amit Shah said: "The government had received a threat email, and we are probing it."

Tension between Hindus and Muslims is acute in Gujarat, a relatively wealthy state. It was the scene of riots in 2002 that left about 2,500 people dead. They were triggered by a fire on a train packed with Hindu pilgrims that killed 60 passengers. The cause was never proven, but Hindu extremists blamed the deaths on Muslims and reacted by rampaging through Muslim areas.