islamabad u.s. official friday say washington deeply concern release house arrest pakistani islamist accuse mastermind bloody 2008 assault indian city mumbai hafiz saeed house arrest since january order free pakistani court week preach friday mosque eastern city lahore u.s. state department spokeswoman heather nauert say saeed organization lashkar-e-taiba responsible deaths hundreds civilians include american citizens pakistani government make sure arrest charge crimes nauert say statement u.s. call pakistan arrest recently free islamist leader