When Ahliana Dicke failed to appear for her eighth grade graduation Friday afternoon, her family grew worried.

What they didn't know was that the 15-year-old girl was lying lifeless on the ground inside the family's northeast Massachusetts home, prosecutors said, dead from apparent gunshot wounds.

Ahliana's young life came to an end when police said someone broke into her Lowell home just after midnight Friday and shot her multiple times.

Less than 48 hours later, Lowell Police Department officers arrested Trevor Bady, 21, of Tewksbury, on criminal charges, including murder, in connection the girl's death.

The town of Tewksbury is about 5 miles southeast of Lowell, south of the New Hampshire state line.

As of Tuesday, a motive in the killing had not yet been determined.

During a press conference Monday, Middlesex District Attorney Marian Ryan and Lowell Police Superintendent Greg Hudon told reporters Ahliana had been "in an abusive relationship" with Bady, whom the prosecutor referred to as the girl's boyfriend.

Hudon called the killing an isolated incident.

"I was on the phone with her last night," the victim's friend, Sklya Gutherie recalled to CBS Boston the day after she was killed. "Still in disbelief. She was happy ... a positive person." Ahliana was excited to enter high school, Gutherie told the outlet and "wanted to do bright things in life."

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'Parents aren't supposed to bury their children'

Those who knew Ahliana expressed condolences to her family on social media Monday after learning an arrest was made in the case.

"This beautiful child did not deserve this," Tareena Pagan posted on Facebook alongside a photo of a smiling Ahliana. "Prayers for the Smith, Dickey, Rivera & Wetherbee families."

Ahliana Dicke never made it to graduation

When Ahliana did not appear for graduation Friday, police said, her family got concerned and attempted to locate her before heading to her home to look for her.

At 6:10 p.m., her grandmother called police to report Ahliana's body had been found inside the family's home. Arriving officers found Ahliana on the floor in a bedroom dead from apparent gunshot wounds. Multiple shell casings were also located at the scene, Ryan said.

Investigators learned the victim had been "in an abusive relationship" with Bady, Ryan said, and he had allegedly "hit and threatened her in the past." Ryan said the victim confided in a number of people that Bady had threatened her as recently as the middle of last week.

Killer took Uber to and from Ahliana Dicke's home

According to a joint press release from police and prosecutors, shortly after midnight Friday, police received a call from a person reporting a male and female fighting outside across the street. The caller reported hearing a female screaming “get off me, get away from me, I don’t want to be with you anymore,” the release continues. The caller also reported hearing gunshots.

Police responded to the scene but did not locate the male or female, but video recovered in the area allegedly showed a female, later identified as the victim, yelling for help shortly before midnight, and a male, soon identified as the defendant, leaving the victim’s home shortly after midnight.

Police also learned the defendant allegedly took an Uber to and from the victim’s home before and after the killing. The Uber driver later reported "he had had a suspicious passenger and expressed concern," prosecutors said, and the passenger was soon identified as the defendant.

On Monday, officers located Bady at a home in Peabody, about 30 miles southeast from where the victim was killed.

According to the release, he was arrested without incident.

Trevor Bady to appear in court on murder charge

In addition to murder, Bady is also charged with felony armed home invasion, unlawful possession of a firearm, unlawful possession of ammunition, use of a firearm while committing a felony and discharge of a firearm within 500 feet of a building.

Prosecutors said Bady was slated to be arraigned in Lowell District Court on Tuesday.

If you are a victim of domestic violence, TheNational Domestic Violence Hotline allows you to speak confidentially with trained advocates online or by the phone, which they recommend for those who think their online activity is being monitored by their abuser (800-799-7233). They can help survivors develop a plan to achieve safety for themselves and their children.

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.