UNITED NATIONS, June 30 (Reuters) - U.N. Secretary-General Ban Ki-moon condemned on Monday the murders of three Israeli teenagers, calling them a "hei**us act by enemies of peace" that aim to entrench division and distrust and widen the Middle East conflict. "There can be ** justification for the deliberate killing of civilians," U.N. spokesman Stephane Dujarric said in a statement, adding that Ban "hopes Israeli and Palestinian authorities will work together to bring the perpetrators swiftly to justice. ...