Question: What is a massacre that occurred as part of an attempt to free a federal prisoner was Vernon C. Miller a gunman in?
Sentence (from "Bernard Coy"): Bernard Paul "Barney" Coy (February 13, 1900 – May 4, 1946) was a bank robber and federal prisoner best known as the planner of a failed escape attempt from Alcatraz prison, on May 2, 1946 which turned into a bloody two day armed confrontation leaving Coy, two fellow would-be escapees and two prison guards dead.
Relevant evidence: No