Captain Marvel mask used in the Brinks robbery.Photo:FBI

FBI
That night, seven masked men quietly broke into the Brinks building in Boston’s North End neighborhood, stealing more than $1.2 million in cash and another $1.5 million in checks from a vault on the second floor after tying up the workers with rope and adhesive tape. One robber wore a Captain Marvel mask to hide his identity, others wore chauffeur’s caps, and they all wore gloves and quiet rubber shoes to help conceal their tracks.
All the employees could do was watch as the robbers pulled off the largest robbery in U.S. history at the time, nearly getting caught when a garage attendant tried to buzz into the building while the robbers were organizing stacks of cash in bags next to the door. Two of the thieves quickly made a move towards the door, likely to try and capture the man. But then he walked away, seemingly unaware of what was taking place inside, according to a historical account of the incident from the FBI.
But after investigators began to identify likely suspects and began to apply pressure on certain members of the group, the tight-lipped bandits began to crack and turn on one another.

AP Photo/Abe Fox
For years, investigators rounded up likely criminals in the New England area: Whiskey bootleggers, gang members, high-rolling gamblers, local racketeers, and other “well-known hoodlums,” the FBI says. Most suspect interviews went nowhere: “If I knew who pulled the job, I wouldn’t be talking to you now because I’d be too busy trying to figure a way to lay my hands on some of the loot,” one suspect questioned in the case had told investigators.
Soon, however, investigators finally caught some breaks.
A police officer in Somerville, Mass., found one of the revolvers used in the robbery, discarded along the banks of the Mystic River. Investigators also soon identified a 1949 green Ford truck with a canvas top that was likely used in the getaway. Nearly two months after the robbery, authorities tracked down pieces of the truck in a dump in Stoughton, Mass., having been torched and cut up into pieces.
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That discovery led investigators to two of the robbers, who lived in the Stoughton area. First, investigators identified Anthony Pino, an immigrant who was known locally among criminals as a reliable “case man,” as well as Joseph McGinnis, a local liquor store owner who Pino was with the night of the robbery.
Through them, investigators were then led to Joseph James O’Keefe and Stanley Albert Gusciora, who were said to be the muscle behind the plot. O’Keefe later proved to be the domino that fell.
He and Gusciora were arrested for a pair of burglaries in Pennsylvania, leading O’Keefe to begin asking former cohorts in the Boston area to help him secure bond in order to be released. Those he asked for help – including Pino and McGinnis – were said to be on “the Big Job” with him, according to the FBI.
Top (left to right) are: Michael Vincent Geagan, 47; Vincent James Costa, 41; Henry Baker, 49. Bottom (left to right) are: Anthony Pino, 48; Joseph F. McGinnis, 52; and Adolph Maffie, 44.Bettmann

Bettmann
Agents continuously visited O’Keefe in jail “in the hope that a wide breach might have developed between the two criminals who were in jail in Pennsylvania and the gang members who were enjoying the luxuries of a free life in Massachusetts,” according to the FBI’s historical account of the investigation. At first, O’Keefe claimed not just innocence, but ignorance about the crime.
O’Keefe would serve his time and be released in early 1954, embarking on a “cold and persistent” mission to pay his “respects” to the others involved in the Brink’s robbery who did little to help him, according to the FBI.
FBI agents and Boston police seized between $70,000 and $90,000 of Brink’s robbery loot in a raid Monday on the office of the B & P contracting company in Boston’s South End.Bettmann Archive/Getty

Bettmann Archive/Getty
Then after visiting a number of former associates, a car pulled up alongside O’Keefe’s vehicle on June 5, 1954 and opened fire. He crouched in the front seat, avoiding the bullets and surviving the attempt on his life. Less than two weeks later, he’d later be shot at again – this time taking bullets in the chest and the wrist. He disappeared from the Boston area on June 16, 1954, only to turn up again in August when he was arrested an hour outside of the city for carrying a weapon.
“During 1955, O’Keefe carefully pondered his position,” the FBI says. “It appeared to him that he would spend his remaining days in prison while his co-conspirators would have many years to enjoy the luxuries of life.”
Burlap money bags recovered in a Boston junk yard from the Brinks robbery.FBI

After nearly another half a year brewing in jail, O’Keefe finally agreed to confess to the crime and told FBI agents in January 1956 what they needed to know about his co-conspirators.
source: people.com