At Tense Time, Pakistan Starts To Test Missiles
Pakistan risks setting off new crisis with India by beginning series of missile tests; Pakistani government denies any provocative intent, and Indian Foreign Ministry spokeswoman dismisses 'missile antics' that she says are targeted at domestic audience in Pakistan; United States says it is 'disappointed' by Pakistan's decision to test missiles, coming day after Pakistan said it would move troops toward India; State Dept issues warning to Americans to defer travel to India and Pakistan because of risk of war; even with Pakistani decision, tensions appear to have lessened; Indian government officials say they will give Pakistan more time, perhaps few weeks, to demonstrate its commitment to stopping infiltration of armed militants into India's side of Kashmir before undertaking any punitive military strikes; photo; map (M)