June 7, 2009 10:06 am SF Death Investigation Questioned Was it a case of murder or an accident? Friends of Hughes De La Plaza are demanding answers on the second anniversary of his death. US & World Videos 0:33 Bay Area man killed in plane crash 2:16 Thousands attend rave in San Jose 1:48 Veterinarian clinic trailer stolen 23:01 NBC Bay Area: We Investigate 26:01 NBC Bay Area: Pride is Universal