lights traveling across the sky at high speed, one stopped and became brighter

A friend and I were sitting on my porch watching the sky.  We saw three lights transverse 1/2 the sky at a high rate of speed (went the whole scope of the sky in a second or two).  on of the lights stopped abruptly and began to become much much brighter.  It then returned to its normal luminescence and exited the sky at the previous high rate of speed.  after this two more of the lights (looked the same as bright stars with the same white light) covered the whole sky at the same rate of speed.  going across the whole sky in a couple of seconds.  i will never forget this experience and have never seen anything like it since.