An 18-year-old high school graduate was shot and killed in Colorado by a close family friend in a “prank that went bad,” according to the victim’s father.

Premila Lal, of Longmont, was supposed to attend Niwot High School’s homecoming football game with her 12-year-old cousin on Friday, but instead decided to return to her family’s home and sneak inside, her father, Praveen, told the Longmont Times-Call.

Her parents, who are in the process of moving to the family to another home in the area to be closer to ailing family members, were not inside the Cambridge Drive residence when Premila and her cousin entered.

Praveen Lal said he left his 15-year-old son and family friend Narrek Galley, 21, to watch the house. He said Premila and the cousin hid in a closet and started making noises to scare the two, and Galley gave a gun to the teen as they proceeded to search the house, the Longmont Times-Call reports.

When Galley found out the source of the sounds, he fired his gun, striking Premila, the Longmont Times-Call reports. Police believe Galley shot Premila because he thought she was an intruder.

“I heard a girl screaming from inside the house. So, I looked out and I saw them coming out. There were three guys and a girl. And they were all running out of the house, screaming, ‘Hurry, hurry. We`ve got to go,’” neighbor Elaine Haddox told KDVR.

Praveen Lal said Galley and his son brought Premila to Longmont United Hospital, where she was later pronounced dead.

"He carried her. Right to the [emergency room] table," Lal said. "After that, the cops separated everybody and I didn't see him."

Galley was arrested by Longmont Police and charged with suspicion of providing a firearm to a juvenile, child abuse and reckless endangerment. He is scheduled to appear in Boulder County court Monday, and police are investigating whether or not to charge him with killing Premila Lal.

“The 21-year-old let a juvenile male have possession of a handgun without the parent’s permission. That is a felony crime in our state,” Longmont Police Cmdr. Jeff Satur told KDVR.

Praveen Lal said Galley and Premila were close friends, the Longmont Times-Call reports.

"I just want to go and tell him we can feel his pain," Praveen Lal said.

The Niwot cross-country team ran a meet Saturday morning in Premila’s honor, writing the initials “PL” on their legs, KDVR reports.

“She graduated with 3.87 GPA with changing three schools. So she was a go-getter. We’re going to miss her,” Praveen Lal told the station.

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