Indian police have detained about 350 people for questioning in connection with the Bombay train bombings, officials said yesterday, amid suspicion that Kashmiri militants could be linked to the attacks that killed at least 200 people.

Most of the detentions were made overnight in Malwani, a northeastern suburb of Bombay, said police Inspector S. Goshal. He said nobody has been formally arrested or charged, and the detainees were rounded up only for questioning to help with the investigations into Tuesday’s bombings.

Bombay police Commissioner A.N. Roy confirmed a large number of arrests had been made but refused to give an exact figure.

“There have been widespread search operations. A lot of people have been detained for questioning,” he told reporters. “This is all part of a large scale investigation, the search operation and combing operation.”

Meanwhile, an Indian Foreign Ministry official demanded that Pakistan dismantle all terrorist networks on land it controls – but fell short of directly accusing India’s nuclear-armed rival for the attacks. Pakistan’s foreign minister denied his country bore responsibility.

Indian Prime Minister Manmohan Singh highlighted the achievements of this city of 16 million, which staggered back to life despite the attacks on the commuter train network.

“Your resilience and resolve will triumph over the evil designs of the merchants of death and destruction,” Singh said in a televised speech. “Let me say again, no one can make India kneel. No one can come in the path of our progress.”

Eight bombs ripped through packed trains at rush hour, stunning a city that sees itself as the embodiment of India’s global ambitions, where the country’s business community and entertainment world come together. The number of dead has risen steadily as rescuers found more bodies and people died of their injuries.

Investigators picked through the mangled ruins of train cars, placing evidence in blue plastic bags beneath an overcast monsoon sky.

“We are just trying to establish what kind of explosives were used and where exactly the bombs were placed, but it appears they were kept in the luggage racks,” said police inspector Yeshwant Patil.

P.S. Pasricha, director general of police for Maharashtra state, earlier dismissed Indian media reports that the powerful explosive RDX was used in the attack, saying investigators were awaiting the results of forensic tests.

Pasricha said investigators were looking into a possible link with Lashkar-e-Tayyaba, a Kashmiri militant group that has denied playing a role in the bombings.

“It is difficult to say definitely as this stage, but Lashkar-e-Tayyaba can be involved going by the style of attack,” said Pasricha.

Lashkar has previously carried out near-simultaneous explosions, according to Indian authorities, who blamed the group for bombings in New Delhi that killed 60 people last year.

A spokesman for Lashkar, Abdullah Ghaznavi, however denied the group was involved.