NEW DELHI: Intelligence agencies have issued an alert about a possible terror strike by Lashkar-e-Taiba in metros, including Delhi and Mumbai, or in border areas of Punjab and Rajasthan The agencies said a group of 20-21 LeT operatives may have entered India from Pakistan and subsequently divided themselves into smaller groups.These men have been trained by Pakistan’s Inter-Services Intelligence, the input said.Police have issued an advisory to ensure tight monitoring and strengthened anti-terror measures at Metro and railway stations, airports, hotels popular among tourists, crowded markets, religious places and stadiums in Delhi, said the advisory. The alert says the infiltrators plan to out a “spectacular terrorist incident,” so as to attract media attention.Intelligence officers suspect the terrorists may carry out a medium intensity blast by a suicide bomber at a crowded location. Police have also been asked to conduct proper frisking and checking, besides tightening security. Earlier in May, a top US intelligence official had warned that Pakistan-based terrorist groups were planning attacks in India while asserting that Islamabad had failed to rein in terrorists.