Hong Kong, April 28 -- Pakistan has closed its airspace to all of India's airlines as tensions escalate between the two countries following a militant attack in the resort town of Pahalgam in India-administered Kashmir. Read More Scores of flights have been cancelled since the closure was announced late last week with some flights taking two hours longer to complete their journeys than scheduled while some aircraft are being forced to make refueling stops en route. "Due to the announced restriction of Pakistan airspace for all India airlines, it is expected some Air India flights to or from North America, the U.K., Europe and the Middle East will take an alternative extended route," Air India said on its website. "Air India regrets the inco...