The location here is Fort MacArthur Museum and related air-raid batteries.  The museum covers the battle in one of its events.

Battle of Los Angeles

The Battle of Los Angeles, also known as The Great Los Angeles Air Raid, is the name given by contemporary sources to the rumored enemy attack and subsequent anti-aircraft artillery barrage which took place from late 24 February to early 25 February 1942 over Los Angeles, California.^[3] The incident occurred less than three months after the United States entered World War II as a result of the Japanese Imperial Navy's attack on Pearl Harbor, and one day after the Bombardment of Ellwood on 23 February.

• http://en.wikipedia.org/wiki/Battle of Los Angeles