The St. Mary’s County Sheriff’s Office says Jaelynn Willey was targeted by her ex-boyfriend at Great Mills High School in southern Maryland. (N/A/Family photo)

A 16-year-old girl shot Tuesday in a Southern Maryland high school by a fellow student has died, according to officials.

Jaelynn Willey was shot in the head in a hallway just before classes began about 7:55 a.m. at Great Mills High School, according to the St. Mary’s County Sheriff’s Office and the girl’s family. The sheriff’s office said in a brief statement that she died at 11:34 p.m. Thursday.

She had been targeted by Austin Wyatt Rollins, 17, after the couple recently ended their relationship, according to previous statements from the sheriff’s office. On Thursday, her family said at a brief news conference that she was brain dead and would be taken off life support.

“My daughter was hurt by a boy who shot her in the head and took everything from us,” said her mother, Melissa Willey.

“She is brain dead. She has no life left in her,” she said, standing beside her husband, Daniel, and carrying one of their younger children in her arms.

Willey’s family spoke Thursday night at the University of Maryland Prince George’s Hospital Center, where she had been brought for treatment after the shooting.

She is one of nine children.

An uncle, Timothy Cormier, on Wednesday described Willey as an “amazing young lady, whose peaceful presence and love of her fellow students and family” is well-known at the school. She was a dedicated student and swimmer, he said.

Rollins was killed after school resource officer Blaine Gaskill confronted the teen as students and staff scrambled for cover. The sheriff’s office said Wednesday that Gaskill fired one shot at Rollins, “who simultaneously fired a shot as well.”

“Rollins sustained a life-threatening injury in the exchange,” the department said.

Rollins used a Glock handgun legally owned by his father, according to the sheriff’s office.

Attempts to reach Rollins’s parents have been unsuccessful.

Desmond Barnes, 14, who also was in the hallway, was wounded by Rollins but was released Wednesday from MedStar St. Mary’s Hospital after surgery on his thigh, officials said.

His mother, Kimberly Dennis, said in a statement Thursday evening that “our entire family is eternally grateful that Desmond is alive, doing well and in good spirits. He is an amazing testimony.”

“We remain deeply saddened and shocked by this shooting incident and continue to pray for the other victim and her family during this difficult time. We are also praying for the entire Great Mills High School family and young people around this country. As a community and nation, we must continue to work and fight for a world that is safe for our children,” she said.

School officials said Wednesday that Great Mills will be closed through the end of the week to assist law enforcement efforts. The school is scheduled to reopen April 2, after spring break.

The shooting at the high school 70 miles south of the District thrust the close-knit St. Mary’s County community into the national debate over gun control and whether teachers should be armed and more armed officers added to improve safety.

The shooting occurred on the cusp of Saturday’s March for Our Lives, a rally against gun violence sparked by the Florida school shooting last month that left 17 people dead.

The Great Mills shooting prompted a lockdown and evacuation at the school of more than 1,600 students. Authorities praised Gaskill, who has been a resource officer at the high school since August, for his quick reaction.

Details of Rollins’s life remained sparse, though the sheriff’s office said it hadn’t “uncovered any public social media posts/threats made by Rollins.”

Friends and neighbors described him as a friendly, happy teenager who liked to play ball, skateboard and hang out with friends.

Newell Rand, a Great Mills graduate who knew Rollins, said he never expected the burst of violence.

“He was a very intelligent guy who had so much going for him,” Rand said in a message on social media.

The shooting has prompted calls to action from the St. Mary’s community.

Rand and other Great Mills students and alumni are planning to travel to the march.

“We are trying to turn a tragedy into a learning experience,” Rand has said in a message to The Washington Post via Facebook. “We hope that some form of action will be taken.”

Aaron Foreman, who was a coach at Great Mills and lives across the street from the Rollins family, posted a Facebook Live video Wednesday morning urging businesses and religious organizations with vans to help take students to the D.C. rally so they could join “their brothers and sisters” from across the nation who are victims of school violence.

“We need to show our children that we believe in them and that their voices need to be heard downtown Saturday,” Foreman said.