What happened at the Battle of L.A.?

On the night of February 24th and early 25th 1942, in Los Angeles California a strange event took place. A UFO was sighted late that night on radar and by eyewitnesses. Since the US was at war with Japan because of the attack on Pearl Harbor the military thought it was the Japanese attacking and unleashed a barrage of anti aircraft fire.  They shot round after round at it and the only thing they hit was their own city. Here is a Video of the event>>>>>http://www.youtube.com/watch?v=U3pXjvDyj8U&feature=related.