The 17-year-old Montgomery County girl accused of attacking another student outside a basketball game Tuesday used a box cutter to inflict six wounds, prosecutors said in court Thursday.

Briana Sarai Funes, a student at John F. Kennedy High School, has been charged as an adult with first-degree attempted murder, assault, reckless endangerment and carrying a dangerous weapon on school property.

The victim, a 17-year-old Montgomery Blair High School student, was treated at a hospital and released, police said.

Funes, a senior, acknowledged that she had stabbed another student during an altercation outside Northwood High School in Silver Spring, prosecutors said. Funes allegedly told police that she saw a friend and the victim fighting in the parking lot and intervened. Funes told police that she pulled the weapon from a jacket pocket and stabbed the victim and then fled in her car, authorities said.

On Wednesday, Funes voluntarily went to a police station and was interviewed by detectives, authorities said. Afterward, she was taken into custody.

According to a prosecutor, officers who transported Funes to a holding facility said she had remarked that “maybe she learned her lesson,” referring to the victim.

Authorities said there was “some underlying dispute” between the victim and Funes’s friend, but they did not elaborate.

Funes, who appeared via closed-circuit television for a bond hearing, answered a judge’s routine questions but did not comment further. Relatives filled a row in the courtroom, and they sobbed when Funes appeared.

During the hearing, A.P. Pishevar, Funes’s attorney, told the judge that the teenager is one of six children. Her father is a painter, he said, and her mother works in janitorial services for the county school system.

Outside the courtroom, Pishevar described the family as humble, honest and hardworking.

Funes was expected to graduate from high school in the spring, and she has been accepted to colleges in Pennsylvania and Virginia, Pishevar said. He said she had worked at a day-care center and had a love for children.

“She is a sweet, pleasant teenager,” Pishevar said. “There is nothing of this nature in her past.”

Funes’s next appearance in court is scheduled for Dec. 22. A judge set bond at $250,000.