Several UFOs were first sighted over Los Angeles, California, on the night of 24 February 1942.
Excerpt from the Wikipedia article, “Battle of Los Angeles”:
“Air raid sirens were sounded throughout Los Angeles County at 2:25 a.m. and a total blackout was ordered. Thousands of air raid wardens were summoned to their positions. At 3:16 a.m. on February 25, the 37th Coast Artillery Brigade began firing 12.8-pound anti-aircraft shells into the air at the object(s); over 1400 shells would eventually be fired [1]. Pilots of the 4th Interceptor Command were alerted but their aircraft remained grounded. The artillery fire continued sporadically until 4:14 a.m. The objects were said to have taken about 20 minutes to have moved from over Santa Monica to above Long Beach. The "all clear" was sounded and the blackout order lifted at 7:21 a.m.”
It was the contemporary news agencies who named the UFO incident, The Battle of Los Angeles.
These videos present radio news reports, photographs and interviews regarding the incident:
http://www.youtube.com/watch?v=B90XD8nG-FU
http://www.youtube.com/watch?v=buVTqwe3DYk
MSNBC TV news report: 65th Anniversary of The Battle of L.A.:
http://www.youtube.com/watch?v=OUL9qsoipFs
The Battle of Los Angeles - Photo analysis by Bruce Maccabee:
http://brumac.8k.com/BATTLEOFLA/BOLA1.html
Wikipedia article: “Battle of Los Angeles”:
http://en.wikipedia.org/wiki/Battle_of_Los_Angeles
The famous 25 February 1942 “Battle
of Los Angeles” photo
(gstatic.com photo)