We were observing planes landing and taking off at mccarren airport from the 23rd floor of new york new york hotel (corner of tropicana ave. and las vegas blvd.) at about an hour after dark, and saw a group of over 12 lights rise from what appeared to be just above ground level near eastern ave. & tropicana ave. they rose and moved slightly northeast where they were observed to be dancing in the sky. (this was between the airport and nellis afb.) their movements were quick and jerky, not like any known aircraft. they moved so fast that it was impossible to count an exact number of objects. after a couple of minutes their lights seemed to dim and fade away as if they were moving away from us in an easterly direction. before, during, and after this viewing, planes were still observed landing at the airport. when i first saw the objects, i didn't think about "what" they were, i was just concentrating on the beautiful and intriguing "dance" that they were performing. after a minute or so, my husband and i realized that it couldn't be any aircrafts that we know of, and it dawned on us that it must be some sort of ufo or orbs. i had a peaceful feeling due to the beauty of the "dance".