A Marine Corps staff sergeant accused of cruelty and mistreatment following an investigation of hazing at the Parris Island training center is facing a preliminary hearing.

The staff sergeant is one of four Marines facing military judicial proceedings this week related to the hazing investigation.

The Marine Corps launched a probe after the March 18 death of 20-year-old recruit Raheel Siddiqui, of Taylor, Michigan, who fell several stories in a barracks stairwell following an altercation with an unidentified drill instructor.

The Marines say those facing charges this week are not connected to Siddiqui's death.

Thursday's hearing at Quantico Marine Corps base is an Article 32 hearing, similar to a grand jury proceeding in civilian court. The hearing should determine whether the Marine will face a court-martial.