Indian anti-terror experts were today piecing together clues from the seven co-ordinated bomb attacks which killed at least 200 rush-hour commuters in Bombay last night to see if they could pinpoint any group as the likely perpetrators of the outrage.

As India's financial hub and its sprawling train network limped back to life, the wreckage of train carriages destroyed in the explosions was taken overnight to a railway shed, where bomb squad officers with sniffer dogs picked through them painstakingly.

Forensic experts were also examining timers found near the scene of the blasts - six of them in first-class compartments - that happened little more than ten minutes apart, leaving more than 700 people wounded. A senior police officer said that an eighth device, which failed to explode, had also been discovered.

Investigators believe that the bombmakers used RDX, a high-quality and very destructive military explosive, or some kind of plastic explosive. A top official from Maharashtra state, of which Bombay is the capital, told AFP that they had also used pencil timers to set the bombs off with such precision.

"We have collected some vital clues in this regard and the Central Forensic Laboratory has been requested to examine them without any delay," he said.

The Indian Express reported that police were looking for two men they suspect may have planted explosives on one of the trains, which exploded at Borivili. It said that police were composing a sketch of a fair, wavy-haired young man who boarded the train and got off in a hurry. The other suspect was wearing a police uniform.

So far, India's political leaders have been careful not to assign direct blame for the attacks and risk fanning sectarian tensions, despite immediate speculation that Islamic militants from Kashmir could be to blame. Pakistan has condemned the bombings.

"Investigations are going on," said D.K. Sankaran, the Chief Secretary of Maharashtra. "So far, we do not have any information linking the blasts to any particular outfit. All media reports are based on guesswork."

But P.S. Pasricha, the state police chief, told reporters at Bombay police headquarters this morning that the attacks bore the hallmarks of Lashkar-e-Taiba (Soldiers of the Pure), a well-organised Kashmiri group responsible for attacks on other Indian cities.

"The modus operandi appears to be similar to Lashkar-e-Taiba," he said. "I cannot categorically say that it was them as those (forensic) reports have yet to come in."

Local papers said police were probing links between Lashkar-e-Taiba and the Students’ Islamic Movement of India (SIMI), a banned organisation that has deep roots in Maharahstra.

But a Lashkar spokesman, Abdullah Ghaznavi, said today that his group was not involved. "These killings are inhuman," he said. "Our jihad is only against the Indian troops in Kashmir. Islam does not allow the killing of innocent people." In Pakistan, Hizbul Mujahedin, a leading umbrella group of guerrilla outfits, issued a similar denial.

R Patil, the deputy chief minister of Maharashtra state, told Indian MPs that 200 bodies had been found in the twisted wreckage of the trains. Bombay is the capital of Maharashtra.

Officials say more than 700 people were wounded. Many remain battling for life in crowded city hospitals, while millions of others were forced to put the threat of more attacks to the back of their minds as they set off on their daily commute this morning. "It’s a little scary but we have no option to go back to work," said Amita Rane, a 24-year-old chartered accountant.

Bombay is not just India's business and entertainment capital but the symbol of its growing links to the West. It has been hit by dozens of bomb blasts over the past decade and a half, including a series of bombings in 1993 that killed more than 250 people that were blamed on the city's largely Muslim criminal underworld.

Peter Lehr of the Centre of the Study of Terrorism and Political Violence at St. Andrews University said that the Bombay bombers could have been inspired by last year's London bombings and the Madrid train attacks on 2004, deliberately choosing a soft target to inflict maximum carnage.

"It is an attempt to instil fear and terror in the minds of the people and spark a new wave of communal violence among Hindus and Muslims. In this they have miserably failed," he said.

Despite the bombings, Indian stocks rose a surprising 3 per cent today, defying predictions of a sell-off. The benchmark index of the Bombay Stock Exchange, the 30-share Sensex, rose 314 points to finish at 10,928.

More than 12 hours after the bombings, relatives of the dead, injured and missing trawled tearfully through the city's hospitals. Many had been unable to start their search last night because of the traffic chaos caused by the attacks.

Manuel Fernandes, looking for his brother, said that he had already travelled to six of the 31 hospitals where the injured were taken. "He was on one of the trains but he hasn’t come home," Mr Fernandes said. "There have been no calls, nobody knows where he is."

Families were ferried to and from the mortuary by staff at the Bhabha hospital, where 22 were certified dead and 72 injured, to try to identify some of the dead. One family emerged after identifying their 19-year-old son. For those who did not find their loved ones alive, authorities waived cremation fees.

Others were wandering around the hospital campus in shock at what happened and examining boards with lists of the wounded. Some sat in corners weeping and others were talking non-stop on their mobile phones giving updates to their families.

Although sometimes considered hard-hearted by other Indians, Bombay residents of all faiths went out of their way to help fellow city-dwellers, offering rides in cars, providing water and biscuits, and taking the dead and injured to hospitals. "We’re used to crises here," said Makarand Bhopatkar, a 35-year-old corporate trainer. "The city survives."

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