A senior UN official said here Thursday that the United Nations headquarter complex in New York \" suffered significant damage in terms of flooding\" from Hurricane Sandy, which hit the metropolitan area on Monday. Gregory B. Starr, the UN under-secretary-general for safety and security, made the statement during a briefing at the UN General Assembly on the effects of the superstorm, described by experts as one of the largest ever that hit the United States. \"We have suffered significant damage in terms of flooding,\" Starr said, adding \"Flooding was at an historic level.\" The flooding was worse in lower levels of the UN complex along New York\'s swollen East River when Sandy hit.