Police say Army veteran Marinna Rollins, 23 (pictured), killed herself. Her body was found early Sunday morning - nine days before she was scheduled to appear in court on animal cruelty charges

North Carolina police are investigating the possible suicide of an Army veteran charged with shooting her service dog as she laughed.

Fayetteville Police Lt. Todd Joyce said Sunday investigators believe that 23-year-old Marinna Rollins killed herself.

Joyce declined to explain what evidence detectives found. He says police were called to her apartment early Sunday around 3am after her body was found by friends, who were having trouble contacting her.

Rollins and her 25-year-old boyfriend Jarren Heng were charged last month with cruelty to animals after investigators say they tied the dog to a tree and shot it multiple times with a rifle.

Cumberland County District Attorney Clark Reaves said the two could be heard laughing on a video recording they made as the dog was killed. That video was later posted to Facebook.

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Rollins and her boyfriend Jarren Heng were accused of tying Rollins' service dog up to a tree and shooting it dead last month. Rollins (left) and Heng (right) pictured above before the act

Rollins' estranged husband Matt Dyer adopted the dog, but Rollins was looking after it while he was on a deployment to South Korea. She had the dog, which she named Camboui, officially made her service dog

Rollins and Heng were arrested after video of the dog's shooting death was posted to Facebook

Rollins' suicide comes just nine days before the two were scheduled to appear back in court. Animals rights activists had scheduled a protest for outside the courthouse the day of the hearing, May 16.

Court documents show Rollins received a medical retirement from the Army in January.

Her family and friends say she struggled with Post Traumatic Stress Disorder after a traumatic experience while serving in South Korea.

Authorities say the dog was adopted by Rollins' estranged husband Matt Dyer, who left the dog he named Huey behind with his wife before being deployed to South Korea for a year.

Rollins (above) was medically discharged from the Army in January. Her family said she struggled with PTSD after something that happened to her during a deployment in South Korea

'I felt like her having to take care of Huey would be good for her and would be good for Huey,' Dyer said, according to WNCN.

While he was away, Rollins had the dog certified as her emotional support dog, and renamed him Camboui.

On either April 16 or April 17, authorities say Rollins and her boyfriend took the dog to a wooded area where they shot it to death.

The two reportedly tied the dog up to a tree and then Heng filmed Rollins shooting the dog to death.

Rollins reportedly laughed in the video and then Heng asked if he could shoot the animal as well. Heng shot the dog five times with a rifle in quick succession.

In the video, Rollins can also be heard saying 'It's been real ... I love you, you're my puppy, you're a good puppy, but...'

Above, the original listing for the dog at a Cumberland County animal shelter

The video then seems to show Rollins dragging the dead dog's body around before burying him in a shallow grave.

'Kind of put him a little deeper,' Heng then appears to say.

The Cumberland County Sheriff’s Office and Cumberland County Animal Control said they found multiple videos of the killing and also text messages talking about it.

A Justice for Cam Facebook site sprang up almost immediately, and a screen grab purporting to be from Rollins' Facebook page shows someone who appears to be Rollins saying 'Great last day with the pooch! Sad he has to go, but he will be much happier where he is heading off to :)'

When confronted by Animal Control officers after the killing, the couple said that the dog cost $75 a week to feed and had some health issues.

Heng was serving in an Army Special Operations Command Unit at the time of his arrest.