UFO Sighting in Las Vegas, Nevada on February 6th 2015 – I noticed these four objects over the Hoover Dam after getting home and reviewing the pics. Hoping you can tell what they are. I thought they might be helicopters, but friend says they’re not allowed to fly that close to each other, so this is unknown.

I took this picture during a visit to the Hoover Dam in Feb of 2015. I hadn't noticed the four objects flying in a straight line until after I got home. I thought they might be helicopters, but I inquired with a friend who is a pilot, and he stated that they are not allowed to fly that close, so he has no idea what these are.