Investigators continue to search for details into the murder of Boston mob boss Whitey Bulger, who was killed inside the Hazelton penitentiary in West Virginia in October. However, several questions remain.

Bulger had been at Coleman II, a federal prison in central Florida, since September 2014. Coleman is reportedly known as a haven of sorts for inmates such as Bulger, a notorious informant, who might need extra protection.

According to The Irish Times, a prison worker said that after Bulger clashed with a female medical worker by refusing some treatment, the former mob boss told the worker that her day of reckoning was coming. His punishment for the threat was a month in solitary confinement. However, instead of being returned to his cell after the month, he languished in solitary for seven more months.

In April, an attempt was made to transfer Bulger to another prison, but the request was denied. According to the code given in the records, the reason for the transfer indicated he needed hospitalization and medical treatment.

Employees at the prison said it was not unusual to punish inmates by moving them to a different prison, and the medical transfer codes may have been used to make it easier to transfer Bulger.

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His medical classification was then suddenly lowered by prison authorities, indicating his health had improved, and thereby making him eligible to transfer to Hazelton.

The transfer request was approved on October 8th, and Bulger was moved on October 29th.

The code in his records at that time indicated the 90-year-old, who used a wheelchair and suffered from heart problems, had completed medical treatment.

In a statement made by the Bureau of Prisons, Bulger was transferred because he had made “a direct serious threat” against a staff member at Coleman, and not because of a medical reason. It is unclear whether the threat referred to in the statement was the one made to the medical worker Bulger had clashed with, or someone else.

The Irish Times reports that a transfer to another facility typically requires multiple approvals. Once the approval is granted, an office in Texas decides which prison the inmate will be sent to and a number of officials must sign off on the move. Once the inmate arrives at the new facility, the staff, including Special Investigative Services, which examines cases of prison misconduct, are supposed to determine whether the newly transferred inmate should be separated from the general population.

The mystery is why so many people at both Coleman and the Texas office would have approved Bulgur’s move to Hazelton, which houses several inmates tied to organized crime and has a reputation for being dangerous to informants.Prison workers also wondered why Hazelton staff members did not separate Bulger from the other prisoners. He would be the third inmate killed at Hazelton this year.

The Bureau of Prisons’ statement said that Bulger’s transfer to Hazelton was made in accordance with its policy. “Based on extensive correctional security observation, (and contrary to published reports), members of crime families are not generally considered to be a threat of harm to one another when placed together in the same federal facility,” said the statement.

Bulger was initially assigned to a cell with Paul J DeCologero, a member of a Massachusetts organized crime group head by his uncle, Paul A DeCologero. For unknown reasons, about an hour after Bulger was assigned to the cell, he was reassigned to a cell with Feliz Wilson. Wilson, a 26-year-old man from Portsmouth, New Hampshire, was serving a 30-month sentence after he had been stopped for riding a bicycle on the wrong side of the road and police found a gun on him. Before his sentencing, Wilson’s lawyer told the court that his client suffered mental health issues and had an IQ of 82.

Also in the same unit at the prison with Fotios (Freddy) Geas, a mafia hit man from West Springfield, Massachusetts, and his cellmate Seam McKinnon, from Montpelier, Vermont, who was convicted of stealing firearms and reportedly has no connection to any crime family.

The morning after Bulger’s transfer, the cell doors were unlocked at 6 am so that inmates could go to breakfast. Sometime between 6 and 8 am, cameras caught video of at least two inmates rolling Bulger into a corner of his cell. He was beaten with a padlock in a sock and was found wrapped in blankets.

According to records, Geas, DeCologero, McKinnon and Wilson were sent to solitary later that day. Geas, whose lawyer said he had a particular dislike for people who cooperated with law enforcement, is believed to be part of the group that participated int he beating. It is unclear if the other three inmates are suspected in somehow being involved in the beating or had only been moved to solitary as a precaution.

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In its statement, the Federal Bureau of Prisons spoke of two assailants,saying that one had “no known ties to any crime family.”

“The alleged assailants were not known to be threats nor had any known geographical ties to Bulger,” the statement said.

The bureau also stated that the “documented legal residence of both individuals” suspected of beating Bulger, “was not Massachusetts” — another mystery given that both Geas and DeCologero were Massachusetts mobsters.

The investigation into Bulger’s death continues.

Whitey Bulger.