(CNN) -- A U.S. Marine accused of hazing a fellow Marine who later committed suicide in Afghanistan has been sentenced to 30 days in jail and a reduction in rank at a court-martial in Hawaii.
Lance Cpl. Jacob D. Jacoby pleaded guilty to assaulting Lance Cpl. Harry Lew in April after Lew fell asleep while on watch after first arriving in Afghanistan.
Charges also were filed against Sgt. Benjamin E. Johns and Lance Cpl. Carlos Orozco III, according to a Marine statement. They will face courts-martial later this year.
"It has been a bad tragedy for us and (we) never can be able to repair our broken heart," said Lew's father, Allen, to CNN affiliate KHON in Honolulu. "We just couldn't believe their own peers could do something like that to their own people."
A military investigation report obtained by the Marine Corps Times said Lew killed himself with a two- or three-round burst from an M249 Squad Automatic Weapon in the early hours of April 3.
According to the Marine Corps Times story on the report, a message found on Lew's arm, believed to be a suicide note, said: "May hate me now, but in the long run this was the right choice I'm sorry my mom deserves the truth."
The incident at Patrol Base Gowragi, in Nawa district, began with Lew failing to respond to radio calls late on the night of April 2, the report said. A sergeant who found him sleeping told others that "peers should correct peers," it said, as reported by the Marine Corps Times.
The report detailed how two lance corporals, whose names were redacted, berated Lew and ordered him to do exercises in body armor for four hours, with one of them stomping on Lew's legs at times.
One Marine kicked and punched Lew until being stopped by another, the report said. Less than an hour later, it said, Lew killed himself.
"At 0343 on 3 April 2011, while crouching down in the fighting position he had just dug, LCpl Lew leaned over his M249 Squad Automatic Weapon as it pointed to the sky, placed the muzzle in his mouth, pulled the trigger, and intentionally killed himself," the report said, according to the Marine Corps Times.
The case drew national attention when Rep. Judy Chu, D-California, the aunt of the Marine who killed himself, told a congressional committee about it in September.
"Harry's death was a heartbreaking tragedy that could have been prevented," Chu said in October. "The decision by the Marines Corps to bring the three Marines before a jury of their peers brings comfort to the family and shows the military justice system at work."
In her September appearance at a House Armed Services Committee hearing, Chu said her nephew's sergeant told fellow Marines in the unit to "teach" the 21-year-old newcomer after he was found asleep on his watch.
"Lance Corporal Lew was beaten, berated and forced to perform rigorous exercise," she said then. "He was forced to do push-ups and leg lifts wearing full body armor, and sand was poured in his mouth. He was forced to dig a hole for hours. He was kicked, punched and stomped on. And it did not stop until 3:20 a.m."
In December, eight soldiers were charged in connection with the October death of another soldier in Afghanistan. Army Pvt. Danny Chen, 19, was found dead in a guard tower, apparently from a self-inflicted gunshot wound.
The eight officers and enlisted servicemen face various charges, including dereliction of duty, making false statements, maltreatment and involuntary manslaughter.
The Army did not specify what alleged acts by the soldiers resulted in the charges, but family members said Chen had complained in letters of harassment by fellow soldiers before his death.
An Army official said the soldiers are essentially charged with hazing and abusing Chen in the weeks and days before he apparently killed himself.
CNN's Tom Cohen contributed to this report.