Surveillance footage of the killing of UnitedHealthcare CEO Brian Thompson shows a gunman brandishing a rare firearm linked to World War II-era weapons.

Investigators believe the shooter used a rare pistol with an integrated silencer, possibly a Brügger & Thomet Station Six, a modern replica of the British Welrod – a silenced pistol designed for covert operations in World War II.

The Station Six, chambered in 9mm or .45 caliber, takes its name from the World War II-era British Station IX, a weapons research and development division that developed the Welrod.

“This is no ordinary firearm,” said firearms expert Steve Wolf Newsweek. “Very few have been produced and they are mainly used for veterinary purposes. It is a modern reproduction of a historical assassination weapon.”

Wolf noted that the weapon used in the attack required manual switching with each shot, mimicking the functionality of the Welrod.

“He fired three shots and three live rounds were recovered, meaning he moved the weapon back and forth six times,” Wolf said. “The ammunition is stored in a magazine, but the shooter must manually pull back and push the slide forward with each shot.”

Known for their whisper-quiet performance, the Station Six and Welrod are manually operated, requiring the user to operate the bolt after each shot. Their design focuses on stealth, making them suitable for covert operations where minimal noise is essential.

The gunman, dressed in dark clothing with a hood and mask, ambushed Thompson in front of New York’s Hilton Midtown. Surveillance video shows the suspect clearing a malfunction in his weapon before firing several shots at Thompson. New York Police Commissioner Jessica Tisch described the incident as a “premeditated, targeted attack.”

As authorities investigate whether the shooter was a professional hitman, Wolf noted that if the gun was a B&T Station Six, that suggests the shooter was likely not a professional. He explained that the weapon’s length and design made it impossible to conceal and that its manual operation required a level of precision and familiarity that the shooter apparently lacked.

Wolf noted several flaws in the shooter’s technique that would be unusual for a professional.

“The way he stood and held the weapon, his driving technique and his general posture suggest he lacked professional training,” Wolf said.

The shooter’s stance included a bent right arm and an extended left arm – the opposite of the proper shooting stance. “His movements were inefficient and he had to manually move the weapon twice during the attack,” Wolf added.

The suspect fled the scene on foot and then hopped on an e-bike, leaving behind limited physical evidence. According to law enforcement, investigators believe he may have left the state and may have arrived in the city on a bus from Atlanta last month.

Police continue to analyze surveillance footage and ballistics evidence and are offering a $10,000 reward for information leading to the arrest of the suspect.