SAN DIEGO (AP) — Police are investigating a huge midnight water-gun fight that left the historic lily pond at Balboa Park trashed and partly drained, causing an estimated $10,000 in damage. At least 1,500 people took part in the fight early Sunday that was organized on social media, the newspaper U-T San Diego (bit.ly/NrQAbp) reported. Organizers specifically urged participants to avoid the landmark lily pond but authorities say some trampled new landscaping, killed koi fish, destroyed ornate floating Victorian lilies, collapsed some planters and broke a pipe that caused the water level to fall drastically.