A car bomb exploded outside a courthouse in Northern Ireland last night, though no one was injured. Phone tipsters warned authorities, but the bomb exploded as police were in the midst evacuating the area. A commander said it was "a sheer miracle" that nobody was killed. An IRA splinter group is believed to be responsible as members seek to derail talks by rival Irish Catholic and British Protestant parties to strengthen their coalition government as London prepares to step out. (More Northern Ireland stories.)