(NEXSTAR) – Police arrested the 33-year-old aunt of two children who were found dead inside of her vehicle during a traffic stop in Maryland Wednesday night, police said.

The woman, identified as Nicole Johnson, had temporary custody of her niece, 7-year-old Joshlyn Johnson, and nephew, 5-year-old Larry O’Neil.

Investigators say Johnson admitted she had been driving around with her niece’s body in the car for more than a year, according to documents obtained by The Baltimore Sun. She allegedly put the girl’s dead brother next to her in May of this year.

“This truly was a devastating incident – one that not only shocked our community to its core, but significantly affected our patrol officers, forensic technicians, and detectives,” Baltimore County Police Chief Melissa Hyatt said in a news release Friday. 

Officers found the two children’s severely malnourished bodies stuffed in the trunk of the car after pulling Johnson over in Essex just after 11 p.m..

After officers told Johnson they would have to tow her car because she was driving without a license and using a fake tag and registration, she replied “it don’t matter, I won’t be here in five days,” the documents said, adding, “Y’all going to see me on the news making my big debut.”

Johnson allegedly admitted to detectives that she became angry with Joshlyn in May of 2020 and struck her multiple times, causing her to hit her head on the floor. The documents state that she placed the girl’s unresponsive body in a suitcase, according to WBAL.

Two months ago, the girl’s brother told Johnson he was tired and and went to lie down but never woke up, she told detectives. She added that he had an injury to his leg but didn’t say how he got it. She said she then put the boy’s body in a plastic tote and placed it next to his sister’s body in the trunk.

The children’s biological mother told police she left them in Johnson’s custody in July of 2019 when she couldn’t care for them after moving to Maryland from Ohio, the documents say. Police said the children’s mother tried to contact them numerous times but was unsuccessful. At one point, Johnson told her sister she would give back the children but never showed up at the agreed on meeting spot, according to the documents.

Johnson faces multiple charges including first degree child abuse that resulted in the death of a child under the age of 13.

“Tonight, the entire Baltimore County Police Department grieves with the community over the unspeakable deaths of two innocent children,” Hyatt said. “The investigation into this atrocious crime will not stop until those responsible are brought to justice.”

The bodies of Joshlyn Johnson and Larry O’Neil were transported to the Office of the Chief Medical Examiner for a full autopsy to determine cause of death.