Editor's note: The accuser has admitted she lied about the attack and cut her own hair. Read the updated story here.

Three sixth-grade boys at a Christian school in Northern Virginia pinned down a black classmate and cut off some of her dreadlocks while telling her her hair was "nappy" and "ugly," she told News4.

Twelve-year-old Amari Allen said the three boys, who she said are white, cut off her hair on Monday. She's a student at Immanuel Christian School in Springfield, Virginia, where Vice President Mike Pence's wife, Karen Pence, teaches part-time.

"They said my hair was nappy and I was ugly," she said.

Amari's grandmother, Cynthia Allen, was stricken as she spoke about the ambush.

"It was like she just died. That's how painful it was for me," she said.

Amari's grandfather also said it hurt him.

"My heart just broke," he said. "I was just paralyzed. I couldn't get myself together."

Though Karen Pence works at the school, the Allens said they did not see any connection between her and the attack.

Head of School Stephen Danish said administrators were "deeply disturbed by the allegations."

"We take seriously the emotional and physical well-being of all our students, and have a zero-tolerance policy for any kind of bullying or abuse," he said in a statement.

Danish said they asked police to conduct a thorough investigation.

Fairfax County Police confirmed Friday they are "actively investigating." A statement from Chief Ed Roessler said Virginia law prohibits the police department from disclosing further information about the case since it concerns juveniles.

Amari — a straight-A student and violin player — said the boys started bullying her at the beginning of the school year. She has attended the school since kindergarten and has always liked it.

But on Monday, she was at recess and about to go down a slide when one of the boys grabbed her and put a hand over her mouth. Another boy grabbed her arms. A third boy cut off some of her hair.

"They put their hands over my mouth. They put my hands behind my back. And they started cutting my hair and saying it was ugly," Amari said.

The bell rang and the boys ran off laughing.

Scared, Amari told no one. On Wednesday, her grandmother was doing her hair when she noticed long portions of it missing. The girl started crying and told the whole story.

The family called Fairfax County police, who took a report of the incident.

Amari's grandparents aren't sending her back to the school until the boys are punished.

"Some consequences should be implemented so that the school will send a strong message: We will not tolerate this, under any circumstances. No matter who you are," Cynthia Allen said, her voice powerful.

Immanuel Christian School is an evangelical private school that explicitly bars its employees from engaging in or condoning "homosexual or lesbian sexual activity" and "transgender identity," as NBC News reported earlier this year.

In January, Karen Pence started teaching art there two days a week after previously working at the school for 12 years.

The office of the second lady did not immediately respond to an inquiry about the incident this week.