Seven deputies from the Los Angeles County sheriff’s gang unit have been placed on leave on suspicion that they belong to a secret clique that celebrates shootings and brands its members with matching tattoos, sources confirmed.

The move is a sign of the intensifying nature of the investigation of the “Jump Out Boys.” Suspicion about the group’s existence was sparked several weeks ago when a supervisor found a pamphlet describing the group’s creed, which promoted aggressive policing and portrayed officer shootings in a positive light.

Days after The Times reported on the discovery of the pamphlet, the captain of the division gathered his deputies for a private briefing, during which he told them that they had shamed the department by forming the group and urged those responsible to identify themselves, a source with knowledge of the unit’s inner workings said.

At some point, one deputy came forward, and named six others, said sources who spoke on the condition of anonymity because the case is ongoing.

All seven of those deputies were placed on leave with pay sometime this week. Internal affairs investigators are trying to determine whether the deputies violated Sheriff’s Department rules or committed serious misconduct.

The deputies under scrutiny have all worked on the Gang Enforcement Team, a unit divided into two platoons of relatively autonomous deputies who target neighborhoods where gang violence is high, locate armed gang members and take their guns away.

Investigators are looking at whether the deputies sported matching tattoos. The suspected design of the tattoo was obtained by The Times and confirmed by two sources: It includes an oversize skull with a wide, toothy grimace and glowing red eyes. A bandanna is wrapped around the skull, imprinted with the letters “OSS” — representing Operation Safe Streets, the name of the larger unit that the Gang Enforcement Team is part of. A bony hand clasps a revolver. Investigators suspect that smoke might be tattooed over the gun’s barrel after a member is involved in a shooting.

One source compared the notion of modifying the tattoo after a shooting to a celebratory “high five.”

Despite the disturbing allegations, sources say there is currently no evidence that the men were involved in improper shootings or other misconduct. Still, the revelations have heightened concerns. What investigators are most concerned about isn’t the alleged tattoos, but the suspected admiration they show for officer-involved shootings, which are expected to be events of last resort.

The department has long grappled with unsanctioned cliques inside its ranks. Last year, the department fired half a dozen deputies who worked on the third, or “3000,” floor of Men’s Central Jail after the group fought two fellow deputies at an employee Christmas party and allegedly punched a female deputy in the face.

Sheriff’s officials later said the men had formed an aggressive “3000" clique that used gang-like three-finger hand signs. A former top jail commander told The Times that jailers would “earn their ink” by assaulting inmates. This week, two former jail supervisors told a county commission created to examine jail abuse about troubling deputy behavior.

One said jailers ignored orders from direct supervisors, preferring instead to listen to rank-and-file deputies who had worked at the jails for several years and earned the informal title of “OG,” short for “Original Gangster.”

Another testified about becoming alarmed by how large numbers of deputies assigned to the same floor made it a habit to arrive and leave work together and not mix with colleagues from other floors. “This is reminiscent of a gang…. This is how gang members act,” said retired Lt. Alfred Gonzales.

The Jump Out Boys, sources said, was a name coined by Compton-area gang members alluding to how quickly deputies from the unit would jump out of patrol vehicles to stop them.

One source with knowledge of the inner workings of Operation Safe Streets said the deputies placed on leave this week consist of current and former Gang Enforcement Team members.

Sheriff’s spokesman Steve Whitmore confirmed that seven deputies were placed on leave, but declined to discuss the details of the probe. “We took the appropriate action and we will continue to take the appropriate action,” he said. “It’s still early in the investigation.”

Whitmore said placing so many deputies on leave over one incident hasn’t happened since the 2010 Christmas party fight involving the “3000" deputies. He said the action is one of the largest mass leaves ever ordered by the department.

robert.faturechi@latimes.com