I just found this interesting bit of info, not sure if it's common knowledge..

"The Man Who Tried to Kill Al Capone"
http://www.nps.gov/alca/historyculture/the-man-who-tried-to-kill-al-capone.htm


Jimmy "Tex" Lucas


In 1934, James "Tex" Lucas was serving 30 years in federal prison for bank robbery and auto theft. The Texas native also had a detainer in his home state that totaled 128 years. Charges included murder, robbery, and escape.
In January of 1935, he and his crime partner Jack Hardin were transferred to Alcatraz from Leavenworth for closer custody. Lucas was 22-years-old.

"Lucas proved to be a troublemaker at Alcatraz. He participated in a work strike in 1936 and was known to engage in clandestine conduct on a consistent basis. On June, 23, 1936, Lucas viciously attacked Al Capone in the shower room. Using half of a pair of scissors, he slashed the Chicago gangster several times. Capone suffered a minor chest wound and superficial cuts to his hands. All Lucas said in his own defense was “Well he threatened to kill me.” He subsequently lost all his good time, 3600 days."


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Mickey Cohen was assaulted in prison

http://www.alcatrazhistory.com/cohen-3.htm

"On August 14, 1963, fellow inmate Burl Estes McDonald, entered an electronics repair training facility and wielding a three-foot iron pipe, snuck up from behind, and bludgeoned the unsuspecting Mickey into unconsciousness. Cohen sustained a critical head injury resulting from shards of skull fragments that had to be removed from brain tissue which had hemorrhaged. Mickey underwent extensive neurosurgery and following a two week coma, doctors inserted a steel plate to replace the mangled bone fragments in the rear skull region."

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of course everyone here knows of the Gotti incident, and others like Genovese putting the hit out on Valachi in the Atlanta federal prison. but what are some of the other incidents in U.S. prisons where mobsters have been assaulted, or even killed?