Federal investigators have determined that the wildfire that leveled much of Pacific Palisades on Jan. 7 was a so-called "holdover" from a smaller fire that was set intentionally on New Year's Day, about a week earlier. After Los Angeles firefighters suppressed the Jan. 1 fire known as the Lachman fire, it continued to smolder and burn underground, "unbeknownst to anyone," according to federal officials. They said heavy winds six days later caused the underground fire to surface and spread above ground in what became one of the costliest and most destructive disasters in city history.