— A 17-year-old girl in the Durham County Detention Center on murder charges in a 2016 shooting killed herself early Thursday morning, according to the sheriff's office.

Detectives with the Durham sheriff's office were dispatched to the detention facility around 3:30 a.m. when detainee Uniece Glenae Fennell was found unresponsive in her cell. Paramedics who responded pronounced her dead at the scene.

Preliminary evidence collected and statements given to detectives indicated that Fennell's cause of death was a suicide, according to the sheriff's office.

Julia Graves, Fennell's mother said she is looking into a lawsuit because she does not believe her daughter committed suicide. She said she spoke to her the same day she died and she was happy and laughing.

"I know my daughter. I just can't see her doing that," Graves said.

She also said she was concerned that her daughter was initially 16 years old in an adult facility.

Fennell was put in the facility on July 26, 2016 after she was arrested and charged with the murder of a 19-year-old Durham man. She was also indicted on Aug. 4, 2016 for discharging a weapon into an occupied residence and discharging a firearm with a pattern of street gang activity.

Posts on Fennell's Facebook page showed that she maintained her innocence, saying she had nothing to do with the murder. In a post from February, she said jail was hard, she wanted to go home and she didn't deserve to be locked up.

An attorney for Fennell on Wednesday had asked the Durham County Sheriff's Office to investigate the jail after he said detention officers were verbally abusive to her and other inmates. He is now calling for an independent investigation into her death.

Friends remember Fennel as being animated and happy even in jail. Her friend, who wanted to be identified only as Benjamin, said he is still in disbelief at the news of Fennell's death.

"Nobody seen it coming, not even her mom. Her mom spoke to her hours before it happened and she was in good spirits. She felt like she was ready to come home. She know she didn't do it," he said.

Fennell's mother is now coping with the loss of two children, as Fennell's twin brother Demoraea Fennell was murdered in November.

"Her mom's not doing good," Benjamin said.

An attorney for Fennell said she was not allowed to attend funeral services for her brother.

The Durham County Sheriff's Office said there were 15 attempted suicides in 2015 and 12 attempted suicides in 2016, but no successful attempts in either year. Data on the number of jail suicides and attempts were not immediately available for 2017.

Officials from the Durham County Sheriff's Office said Fennell was not under suicide observation prior to her death.

Benjamin hopes Fennell will be remembered as innocent and loving.

"Nobody believes that she did it, honestly," he said.

The Durham County Sheriff's Office will notify the State Bureau of Investigation in compliance with standard protocol. The State Medical Examiner will conduct an autopsy.