<span style="color: #222222;">Punjab Police has arrested the second and main perpetrator of the Nirankari Satsang Bhawan grenade attack, Avtar Singh, to crack the case completely in less than a week after terror was unleashed on innocent victims at Amritsar's Adliwal village. </span><br />'' <br />'' <span style="color: #222222;">The blast had claimed three lives and left 16 injured. Avtar would be produced in the court and the police would seek his remand, DGP Suresh Arora disclosed at a media conference on Saturday.</span><br />'' <br />'' <span style="color: #222222;">He said that there was strong evidence against the suspects caught in the case. He said that Avtar's links have also been traced to Harmeet Singh Happy, the self-styled chief of ISI-backed KLF, based in Pakistan. </span><br />''