Admitting that there was no credible intelligence input on the Mumbai attack, home minister P Chidambaram on Thursday did not rule out any angle, including the possibility of an attempt to derail Indo-Pak talks, behind the blasts.

Expressing "deep regret" to the people of Mumbai over the incident, he said the probe will not start on any "pre- determined assumptions" and will cover every terror group that has the capacity to carry out such strikes in the country.

Chidambaram said there was no intelligence failure on the part of central and state agencies.

"There was no specific intelligence input on this...whenever there is an intelligence, we share it with the states," he told a 70-minute press conference here.

"We are not ruling out any angle. We will probe (the involvement of) every terror group...The investigations into the attack will not start on pre-determined assumptions," he said.

He was speaking after a high-level meeting with Maharashtra chief minister Prithiviraj Chavan and senior ministers and officials to review the situation in the wake of the serial blasts that left 18 people dead, including a severed head that is yet to be idenitified, and 131 injured.

Union home ministry had officialy stated in its first bulletin last night that the death toll was 21.

Asked whether the blasts were an attempt to derail the Indo-Pak talks later this month, Chidambaram said that every angle will probed in the case.

"I do agree that the Indo-Pak talks will be held this month, in ten days from now. We are not ruling out any angle. We will probe every angle," he said.

The home minister also said that India was living in the "most troubled neighbourhood" as Pakistan and Afghanistan are the "epicentres" of terrorism.

Giving details about investigations carried out since last night, Chidambaram said ammonium nitrate, an explosive substance, was used in the IEDs which had timer devices.

He ruled out the use of remote control to trigger the blasts in Zaveri Bazar, Opera House and Dadar areas in Mumbai.

In Dadar, he said, the explosive material was planted in a bus shelter, at Opera House the bomb was on the road that left a deep crater while in Zaveri Bazar it was kept in a motorcycle.

"No group has so far claimed responsibility for the blasts," Chidambaram said, while making it clear they were not aimed at any particular community.

Terming the attack as a "coordinated strike", he said, "Whoever perpetrated this attack has worked in a very, very clandestine manner."

He said among the 131 injured, who were taken to 13 hospitals, 26 were discharged after treatment, 82 are in a stable condition while 23 people are in a serious condition.

Of these, some are in critical state, he said.

To a question, the home minister said that the target is India's "unity, integrity and prosperity" and assured that "every foreigner in India is safe."

"If an incident like this happens, let me assure you it is not targeted against any foreigner or tourist visiting India. It has happened at some places on last occasions as some foreigners were present in hotels. Therefore, they lost their lives," he said.

He said while the explosions at Opera House and Zaveri Bazzar were "high-intensity", the one in Dadar was of low-intensity.

Chidambaram said police forces face inherent difficulties in high-density areas of the mega metropolis and it is prevalent in every part of the world.

To a specific question, the home minister said every city in India is vulnerable (to terror attacks) and Delhi was no exception.

About an e-mail from an organisation with regard to Mumbai blasts, he said, "That was not a serious one."

"It is highly unfortunate that two terror incidents have happened after 26/11 attacks and both of them are in Maharashtra (Pune in February, 2010 and Mumbai)," he said, adding that the security agencies of the central and state governments had been closely monitoring the situation including holding review meetings on May 19, June 9 and June 29 this year.

Appreciating the "splendid response" of the people in Mumbai, he said he was happy to note that children were going schools and people getting back to work after the attack last night.

The blast sites have been cordoned off and public banned from visiting them.

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UNSC, world leaders condemn terror strike in Mumbai

United Nations

UN security council and world leaders have strongly condemned the Mumbai serial blasts that killed 21 people and injured 141, saying terror acts are "criminal and unjustifiable, regardless of their motivation."

UN chief Ban Ki-moon joined countries across the world including the US, Russia, the UK, France, the UAE and Pakistan in condemning the terror strike in India's commercial hub.

"The members of the security council reaffirmed that terrorism in all its forms and manifestations constitutes one of the most serious threats to international peace and security, and that any acts of terrorism are criminal and unjustifiable, regardless of their motivation," said a statement read out by Peter Wittig, Germany's ambassador to the UN and current council president.

The council expressed its deep sympathy and sincere condolences to the victims of these "heinous acts" and to their families, and to the people and government of India.

A statement from the office of the UN chief said, "The secretary-general (Ban) condemns the attacks that have killed and injured many in Mumbai. No cause or grievance can justify indiscriminate violence against civilians. The secretary-general expresses his solidarity with the government and people of India, and extends his sincere condolences to the families of the victims."

In Washington, US president Barack Obama condemned as "outrageous" the attacks in Mumbai and offered support to bring the perpetrators of the "terrible crimes to justice".

"I strongly condemn the outrageous attacks in Mumbai," Obama said in a statement.