A switch which is believed to have been used to trigger the briefcase bomb outside the Delhi high court was found on Saturday. But a breakthrough in the probe still eluded investigators three days after the deadly explosion.
As investigators struggled to find conclusive leads in the blast case, they are now looking into the possibility of whether Indian Mujahideen operatives were helped by some other groups in carrying out the attack, which left 13 dead and 88 injured.
Sources said that a switch used in the bomb was found by investigators. But the timer device, if at all used, is yet to be recovered.
They said the anti-terror squads of various states were working on the case but none of them had got any substantive leads.
The investigators were not ruling out the possibility of IM cadres being helped by some other group on the basis of a comparative analysis of July 13 Mumbai triple blasts and the high court blast, since components found in the bombs were identical.
Investigators also suspected that some of the 11 fugitive IM operatives, who were allegedly involved in 2008 Delhi serial blasts, may have played a part in the high court blast.
Four men -- two each in Alwar in Rajasthan and Mumbai -- were detained by the police since they resembled the sketches of possible suspects released by the Delhi police. But they were freed after questioning and getting their identities verified. The two men detained in Alwar hailed from Anantnag in Jammu and Kashmir.
The questioning of the six men detained in Kishtwar in Kashmir continued. They included the owner of the cyber cafe to which the Harkat-ul-Jihadi email claiming responsibility for the blast was traced.
The detained included Sohaib, whose parents claimed that their son was innocent and "not involved at all" in the blast. He has been detained for purportedly sending the HuJI email.