Investigators on Thursday probed “every possible hostile group” in their search for culprits behind the Mumbai terror attack and the involvement of a suicide bomber was not being ruled out.

As Mumbaikars slowly came to grips with last evening’s three serial blasts, no specific leads emerged and authorities did not want to speculate on who could be involved merely saying that “all angles” are being probed.

Union Home Minister P. Chidambaram made it clear that it was too early “to point a finger at any one group”.

All groups “hostile to India” are on the “radar” in the probe, he said.

The Minister revised the death toll to 18 including a person with a severed head from 21 which was put out in an official list released by the Ministry. As many as 113 persons were injured of whom 23 are in a serious condition

Mr. Chidambaram rushed to Mumbai to review the situation and told reporters that ammonium nitrate, an explosive substance, was used in the Improvised Explosive Devices (IED) triggered by timer devices to carry out the “well coordinated” terror attack.

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

Addressing a 70-minute joint news conference with Maharashtra Chief Minister Prithviraj Chavan, Mr. Chidambaram said “there was no “intelligence failure” on the part of central and State agencies to warn of an attack.

Asked whether the explosions were timed to disrupt the India-Pakistan Foreign Minister-level talks this month end, he said, “We are not ruling out anything. That angle will also be kept in mind.”

After his review meeting in Mumbai, he said, “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.”

“Whoever perpetrated the attack has worked in a very, very clandestine manner. Maybe it’s a very small group, maybe they didn’t communicate with each other,” he said.

“I am confident that ... we will be able to zero in on the group that caused these bomb blasts,” he added.

In New Delhi, Union Home Secretary R.K. Singh did not rule out the involvement of a suicide bomber.

“The NSG DG has informed that a body with circuit has been found from one of the sites. The body was found near the explosion site. We are not ruling out anything,” he told reporters in New Delhi.

Mr. Singh was replying to a question about the possibility of involvement of a suicide bomber in the blasts as the body was found with a circuit near one of the blast sites.

Maharashtra Anti-Terrorism Squad (ATS) chief Rakesh Maria said it was too early to say whether a “human bomb” was involved.

On the possibility of cross border links with Wednesday’s blasts, Secretary (Internal Security) in the Home Ministry U.K. Bansal said, “As of now there is no ground to believe that there is any link of anyone from across the border.”

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