The Jammu and Kashmir police claim to have made a breakthrough in the Delhi terror threat case, with the detention of a suspected LeT operative hailing from Srinagar. Quoting police sources PTI said that Umar Zargar, the Kashmiri youth, made the telephone calls at the behest of the Pakistan-based Lashkar-e-Toiba, warning that blasts would be carried out in the crowded markets of Delhi. Highly-placed sources in the Jammu and Kashmir Home Department said that the man was detained in the wee hours yesterday, after a massive manhunt was launched to nab him.<br/>