Speculation regarding the serial blasts continued on Thursday with the authorities not ruling out the possibility of a human bomb, a timer device or cellphone alarm being used to detonate the bombs.

However, there was no clarity on any of these assumptions with the police even refusing to confirm that the blast was the handiwork of terror outfit Indian Mujahideen. With no terror outfit claiming responsibility for the blasts even 24 hours after the incident, the home ministry treaded cautiously, saying “nothing is being ruled out” and that all terrorist and anti-national outfits are being investigated.
U.K. Bansal, secretary (internal security), ministry of home affairs, said it is not a “blind investigation”. “We are confident that some lead will soon emerge,” he said.
Earlier, the discovery of a body with wires embedded in it near the Zaveri Bazaar blast site had given rise to speculation that a “human bomb” may have been used to trigger the blasts. “The National Security Guard D-G has informed us 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,” Union home secretary R.K. Singh said. However, JJ Hospital dean T.P. Lahane later clarified that the body was identified and handed over to family members. “What we found was a circuit, and not a detonator. We have handed it over to the police,” Dr Lahane said.
Mr Bansal said there could be several reasons that a circuit was found embedded in the body of one of the victims. “One possibility is that the person concerned might have been standing near the bomb and as a result some parts of the bomb got embedded in it (the body). There is another possibility: that it could have been planted on his body,” he said. Mr Bansal also said that there is no evidence as yet to establish the involvement of crossborder terrorist outfits.
The home secretary said the bombs were “not crude in nature and it is believed that trained persons were involved in making the bombs”. He said explosive experts from the Central Forensic Science Laboratory, the NSG and Mumbai police were examining the blast sites and, according to the information available, ammonium nitrate had been used in the bombs.
While the police said that prima facie it seemed that a timer must have been used to detonate the bombs, there was speculation about cellphone alarms being used as detonators.
Another theory was that a group of 22 operatives of the Indian Mujahideen from Andhra Pradesh had carried out the blasts. Union home minister P. Chidambaram on Thursday had said that a small group appeared to be behind the attack.
Sources said intelligence inputs that a group of 22 operatives had left Andhra Pradesh for Maharashtra had been ignored. “The group was basically disgruntled with the educated and affluent members of the outfit, who were computer-savvy and were working in corporate offices. They felt their ideology was being lost because of these members and hence decided to form their own group and carry out the attacks. This is also why there was no email sent claiming responsibility for the attack,” said a source.
Another theory pointed to the participation of Mohsin Chaudhry, who had played a vital role in the Pune German Bakery blast and has been absconding ever since. According to sources, Chaudhry may have used an IM sleeper cell to carry out the blasts.
The Anti-Terrorism Squads of Gujarat and Rajasthan have intensified their drive to identify the IM sleeper modules in their respective states. “Investigators are also planning to question Salman and Shazad, both suspected IM militants arrested in connection with the Delhi serial blasts. Their questioning may provide the agencies with clues,” sources said.
Security agencies are also probing a Bangladesh link to the bomb attacks. According to sources, the agencies are questioning some Bangladeshi nationals in Surat, Gujarat. “Their statements are being verified. Inputs with the Central agencies confirm IM modules are active in several districts of Gujarat, including Surat,” sources said, adding that these IM modules have handlers in Bangladesh and Pakistan.
Meanwhile, government sources said the CPI(Maoist) cadres recently arrested in Pune had fled West Bengal when the former Left Front government intensified its crackdown on Maoists before the Assembly elections. The sources, however, said Maoists have so far not attacked any metropolis and doubt they had any role in Wednesday’s Mumbai blasts.