Notorious Boston gangster and convicted killer Whitey Bulger was brutally murdered on Tuesday at a high security penitentiary in West Virginia.

And the way he was purportedly killed is stomach-turning. (RELATED: Infamous Mobster James ‘Whitey’ Bulger Found Dead After Prison Transfer)

According to TMZ, Bulger was jumped by a group of three inmates just a day after he had transferred from a prison in Pennsylvania to the U.S. Penitentiary Hazelton in Bruceton Mills, West Virginia.

One inmate allegedly beat him with a padlock in a sock, then another tried to gouge his eyes out with a makeshift shiv. He was beaten until he fell out of his wheelchair, unconscious and badly bruised on his head.

EXCLUSIVE DETAILS: Boston Crime Boss Whitey Bulger Beaten to Death in Prison https://t.co/mWmAaeaAv7 — TMZ (@TMZ) October 30, 2018

The prisoners reportedly wheeled him to the corner of the room so the attack would not be picked up on surveillance video.

He was then found unresponsive at 8:20 a.m.

Gouging one’s eyes out, TMZ points out, is a trademark signature of 1940s mobsters. They apparently do this to informants and snitches as a warning message to others who may be considering ratting out their buddies.

Beginning in 1975, Bulger served as an informant for the FBI over the years. But he didn’t exactly live an otherwise clean life. He’s been linked to at least 11 murders and was finally sent to prison in 2013 for 31 counts, including racketeering, extortion, drug dealing and possession of weapons over more than a decade.

Bulger was 89 years old, serving life in prison.

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