Raheel Siddiqui, 20, died at the Marine Corps recruit depot at Parris Island, S.C., while in initial training. (Courtesy of the Siddiqui family)

The Marine Corps is investigating allegations of hazing, physical abuse and assault against 15 drill instructors at the Parris Island recruit depot, Marine officials said Wednesday, broadening the scope of a probe first disclosed after the death of a Muslim recruit in March.

The investigation centers on the installation’s 3rd Recruit Training Battalion, and was launched at Parris Island in November, Marine officials said. Other allegations, including failure to properly supervise recruits, also have been made.

The growing scandal is likely to rock the service, which considers the training depot in South Carolina to be hallowed ground. All enlisted female recruits undergo initial Marine training there, as well as all male recruits born east of the Mississippi River. Already, at least two Marine officers have been removed from their jobs.

Maj. Gen. James W. Lukeman, commanding general of Training and Education Command in Quantico, Va., is expected to decide on discipline for those involved, according to a news release distributed Wednesday evening. The Washington Post first reported earlier this month that drill instructors had been removed from their duties, while the Wall Street Journal reported Wednesday the nature of the allegations they face.

“We take every allegation of misconduct very seriously and will review each investigation carefully,” Lukeman said. “The safety of the recruits and the integrity of the Marine Corps recruit training program are among our top priorities and, once the investigations are complete, we will take necessary administrative and judicial action as warranted to ensure proper accountability.”

The investigation became public knowledge after the March 18 death of Raheel Siddiqui, 20, a Pakistani American recruit from Taylor, Mich. Marine officials said Wednesday that during the course of an investigation into Siddiqui’s death, “facts revealed a drill instructor was improperly placed in charge of recruits while he was subject to an ongoing investigation.

“Existing orders, policies and procedures to prevent improper assignments were not followed,” the Marine Corps’ statement said. “Interim corrective actions have already been taken.”

One senior drill instructor involved in supervising Siddiqui had previously faced allegations of putting another Muslim recruit in a clothes dryer and using racially charged language, the Wall Street Journal reported, citing anonymous Marine Corps officials.

Siddiqui arrived at the depot March 7, and fell 40 feet to his death after running out of a squad bay and jumping over a stairwell railing. He had just been revived after fainting during a military drill. A lawyer representing the Siddiqui family, Nabih Ayad, previously told The Post that the family thinks a drill instructor “smacked” him moments before his death.

Rep. Debbie Dingell (D-Mich.), whose district includes Siddiqui’s hometown, has previously pressed the Marine Corps for answers on what occurred and specifically asked whether the recruit had been hazed. Marine officials declined to provide specifics, citing the open investigation.

The officers already removed from their jobs include Lt. Col. Joshua Kissoon, who oversaw the 3rd Recruit Training Battalion, and his superior, Col. Paul D. Cucinotta. Kissoon was relieved of his command March 31, after Siddiqui’s death, while Cucinotta was removed by Lukeman earlier this month. Cucinotta’s senior enlisted adviser, Sgt. Maj. Nicholas Deabreu, also was removed.

The commanding general during the period covered by the investigation was Brig. Gen. Terry Williams. He has since taken a new assignment at the Pentagon.