(CNN) -- When James Huberty walked into a McDonald's restaurant 25 years ago this month, he knew he was going to kill somebody. He probably didn't know his murderous rampage would change how police departments work. Police help a wounded customer out of a California McDonald's where a man killed 21 people in 1984. At 3:40 p.m. on July 18, 1984, Huberty carried a long-barreled Uzi, a pump-action shotgun and a handgun into a McDonald's in San Ysidro, an enclave of San Diego, California. Witnesses said the unemployed welder and security guard started shooting immediately, and kept on shooting for 77 minutes until a police sniper on a nearby rooftop ended the siege with a bullet through Huberty's heart.
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Rampage at San Ysidro, California, McDonald's killed 21
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Police were outgunned by one man with high-powered weapon
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First cop on scene recalls being pinned down by barrage from Uzi
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Afterward, police department beefed up elite tactical unit, added counseling
After @placeholder, the department created a dedicated unit that trains continuously and uses much more formidable weapons and tactics.