thug (n.)

1810, "member of a gang of murderers and robbers in India who strangled their victims," from Marathi thag, thak "cheat, swindler," Hindi thag, perhaps from Sanskrit sthaga-s "cunning, fraudulent," from sthagayati "(he) covers, conceals," from PIE root *(s)teg- "to cover."

https://www.etymonline.com/word/thug

The first reference to thugs dates back to the writings of Ziau-d din Barni, a Muslim political thinker and writer, in 1356.

The original thugs were members of the Thuggee tribe, a professional class of organized criminals who swindled, robbed, and murdered travelers across the Indian subcontinent from as early as the 14th century. Tracing their origins back to seven Muslim tribes, both Muslim and later Hindu members worshipped Mother Kali, the goddess of destruction.

https://allthatsinteresting.com/thuggee-thug-origin

The Thugs were a secret cult that worshipped Kali, Goddess of Death. According to the Thugs, Kali’s favor came at the cost of regular payments in blood. The Thugs gave it to her. In all the centuries of their existence, few Thugs provided as much blood as Thug Behram.

Behram was a particularly gifted strangler. His preferred tool was the cloth sash he wore on his waist. Inside, Behram had sown a heavy medallion. Behram could throw this medallion around the victim’s Adam’s apple, allowing him to strangle them with deadly force.

Behram probably operated as a Thug for decades. But by the early 1830’s the golden age of the Thugs was crashing to an end. The British, who had colonized India, now turned their attention to the group under superintendent William Henry Sleeman.

Sleeman used a classic tactic against organized crime groups, granting certain Thugs immunity for their crimes if they informed against the others. Now, it was the Thugs that didn’t know who they could trust. Within a decade, a criminal organization that had lasted for centuries was destroyed.

Until the end, the Thugs warned that the killings had been necessary, according to contemporary accounts. They were sacrifices to Kali to prevent her from destroying the world. But ultimately, Thugs like Behram were probably motivated more by simple greed than religion. And that greed drove them to commit some of the most horrific mass murders in history.

https://allthatsinteresting.com/thug-behram