Secretary General Ban Ki-moon emphasized the need to avoid an escalation of tensions amid the recent abduction of three Israeli teenagers and the increased violence and mass arrests in the occupied West Bank, the United Nations said Sunday. The men reportedly were abducted near Hebron two weeks ago, and more than 200 Palestinians have been detained in Israeli security operations the West Bank since then. It was imperative, for both political and security reasons, not to react to provocations in a manner that would further escalate tensions, the secretary-general said, adding that he expected all sides to exercise restraint and observe human-rights standards and international law.