A New Hampshire community is mourning the loss of a popular high school student and athlete who was killed in a traffic accident on Interstate 93 on Friday.

Lillianna Cawthron, 17, of Londonderry died when her car left the highway and struck several trees Friday afternoon, state police said.

According to a post on Londonderry High School’s Alternative Education Programs Facebook page, Cawthron was an ambitious student and dedicated athlete, and she would have started a new school year on Tuesday when classes resume in the fall.

“Our program and Lancer Nation have lost the sweetest, bravest soul,” school officials said in their Facebook post.

“Lillianna was an incredible student with a bright personality who could light up any room she entered,” school officials said. “As a member of Lancer Nation, she was a dedicated athlete in our cross country and track and field programs, as well as a talented alto saxophonist in our marching band.”

“Her infectious laugh and bubbly personality enabled her to maintain impactful relationships with friends and family, whom she loved very much,” school officials said. “She was a strong advocate for her own needs and the needs of others, which was evident in her work with children at The Learning Tree.”

“Always ambitious, Lilana is scheduled to graduate from the adult education program a semester early in January 2025,” school officials said. “Lancer Nation will forever cherish the memories of her infectious smile, wit and zest for life. Our thoughts and prayers are with her entire family.”

On Friday at 2:47 p.m., state police officers were called to a crash near mile marker 14 on Interstate 93 southbound.

When police arrived and spoke with witnesses, they found that a gray 2008 Mercury Milan was traveling southbound when it veered right off the highway and struck several trees.

Cawthron was taken by ambulance to Elliott Hospital in Manchester, where she later died, state police said.

“It is with deep sorrow and sadness that I share this post,” Margaret Healey, Cawthron’s great aunt, said in a Facebook post on Sunday. “My great niece Lillianna Cawthron, age 17, tragically lost her life on Friday due to injuries sustained in a car accident. A young life was taken from us far too soon.”

Several people paid tribute to Cawthron in posts on Facebook.

“I just can’t believe it. This girl lit up the room whenever she walked in. She always made a point to say goodbye to me before leaving work and was always one of the first people to greet me when I walked in,” wrote Allyson Elise.

“My heart and soul go out to her family,” Elise wrote. “I am sad for all who had the pleasure of knowing her. Lillianna Cawthron was too young and will be missed forever.”

“A wonderful young man has left us far too soon,” wrote Erica Miethner Harlow.

Siobhan Smith wrote: “A devastating loss for everyone who had the pleasure of knowing her. Lilliana’s laugh was infectious and her smile lit up every room she entered.”

“Countless times her quick sarcasm and conversation while stealing a treat or two made my day more than she knew,” Smith wrote. “We will miss you so much, Lilliana.”

This is a developing story. Check back later for updates as more information becomes available.

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