NEEDHAM — As teachers and students cried inside Needham High School on Monday, the anguished father of one of two classmates struck and killed this weekend as they crossed the street was left searching for answers.
“We don’t understand what happened,’’ said Craig Newfield, whose daughter Talia was killed Saturday when she was hit by a car near the high school. “We don’t understand how two beautiful young women can get taken from us in the space of about 20 feet on a clear evening on a flat, straight street in Needham. We just don’t understand.”
Police continued their investigation Monday into the deaths of Newfield, 16, and Adrienne Garrido, 17, who died after a collision involving two vehicles on Webster Street in this quiet suburb west of Boston. The teenagers, who were best friends, were using a crosswalk when they were hit, authorities said.
On Webster Street, a memorial of flowers and other remembrances grew steadily throughout the day. Neighbors stopped and wept. Others asked how such a tragedy could occur.
“These kids had their whole lives and the whole world to look forward to,” Newfield said. “It’s all been taken away for absolutely no reason.”
Two vehicles were involved in the fatal crash, which happened around 5 p.m. near the back entrance to the high school. The drivers of both vehicles — a Cadillac sedan and a Nissan Sentra — remained at the scene and spoke with police, the Norfolk District Attorney’s Office said. The drivers, whose identities were not released, are not Needham High students and are not high-school age.
On their first day back at school since the fatal crash, students struggled with their emotions, school officials said. Grief counselors were available there.
“Many students knew the girls and are upset about the loss of dear friends, and others were not as familiar with the girls but know that their friends and teachers are aching,” said Superintendent Daniel E. Gutekanst. “They are wondering how best to react and respond. It’s tough up there right now.”
Gutekanst said the two girls — “energetic, athletic, caring, loving daughters, sisters, and friends” — were well-known among their fellow students.
After the crash, Newfield was taken to Beth Israel Deaconess Hospital-Needham and pronounced dead Saturday, officials said. Garrido was transported to Beth Israel Deaconess Medical Center in Boston, where she died of her injuries Sunday, authorities said.
Funeral services will be held for Newfield at Temple Aliyah in Needham on Tuesday. Her family, which includes three siblings, is planning a memorial observance at a later date.
“Talia was a wonderful daughter, sister, and friend,” the Newfield family said in a statement released by the Needham schools. “She was everything that we could ever have asked for, and more than we knew.
“She was righteous, talented, smart, funny, and enigmatic, with great positive impact on our lives and those around us, and with huge potential.”
Garrido and Newfield ran for the school’s cross-country team for three years. Garrido also participated in indoor and outdoor track, said Daniel Lee, Needham High School’s athletic director. At a meet on Sunday, the indoor track team wore black-and-white ribbons with “TN & AG” written on them to honor the girls.
Lee said that “words cannot express” how much the two students meant to their teams, their school, and the Needham community.
“This was a challenging and emotional day for the athletes, coaches, and everyone whose life had been touched by Talia and Adrienne. They were two special girls, who will be truly missed by all who knew them,” Lee said.
A photo posted on Facebook showed the friends standing side by side, smiling broadly at the edge of a pond. Garrido wore a Needham High track uniform; Newfield, a Cape Cod sweat shirt.
“Rest in peace, Talia and Adrienne,” the post read. “You will be missed.”
Inside Needham High School, emotions were raw as teachers cried and grieving students gathered in the library, said Steven Leicht, a 16-year-old junior.
Luca Mancino, a freshman, said the typical bustle and buzz in the hallways was gone.
“I didn’t really know them, but it’s just taking a hard toll on all of us. It’s really made us appreciate everyone else around us,” the 14-year-old said. “Everyone was super tense. You could just feel that something terrible had happened.”
Sophomore Rachel Hurwitz, 15, said midterm exams were postponed because students and teachers were so upset.
Outside the school, a mother of a Needham High junior paused at the crosswalk and memorial.
“We’re all heartbroken,” she said, asking not to be identified. “Both of the girls were so loved by their classmates . . . they’re going to be so missed.”
The junior class is a tight-knit group, she said. “Our kids have grown up together. It’s just devastating,” she added.
Throughout the day, groups of Needham High students visited the memorial. Some laid bouquets of flowers. Others stood silently, looking at photos of their two classmates. One woman with two children at the high school struggled with her emotions as she walked nearby.
“It’s shocking. We walk here every day,” she said, her eyes filling with tears. “Our kids are really struggling.”
Aimee Ortiz of the Globe staff and Globe correspondents Andrew Grant, John Hilliard, and Jeremy Fox contributed to this report. Brian MacQuarrie can be reached at email@example.com. Emily Sweeney can be reached at firstname.lastname@example.org. Follow her on Twitter @emilysweeney. John R. Ellement can be reached at email@example.com. Follow him on Twitter @JREbosglobe.