An unidentified man leaped to his death about 8:30 p.m. Friday from a third-story walkway at Horton Plaza.
San Diego police said about 20 shoppers witnessed the man's jump from a walkway outside Mervyns department store to the center of the mall's Chelsea Court area three stories below.
Mall security personnel cordoned off the south end of the shopping center. There are no shops yet in that portion of the center and no stores were forced to close early, said Bob Dobson, Horton Plaza general manager.
Witnesses told police they saw the man talking to himself before he jumped from the walkway, said Sgt. L.D. Martin of the central patrol division. The deceased man was carrying no identification.