An ongoing Associated Press investigation has uncovered deep, previously unreported flaws within the Bureau of Prisons over the last few years, including widespread criminal activity by employees, dozens of escapes, the free flow of guns, drugs and other contraband, and severe understaffing that has hampered responses to emergencies.

Alcatraz, a notorious former prison on an island in San Francisco Bay, once housed some famous gangsters like Al Capone and George "Machine-Gun" Kelly.