A 17-year-old girl was critically injured Friday evening when the moped she was riding crashed into a guardrail on Farrington Highway in Waianae, police said.

At about 6:47 p.m., the teen was traveling south on Leihoku Street when “she attempted to execute a left turn at the intersection of Farrington Highway, and collided with a metal guardrail, ejecting the juvenile female onto the grassy shoulder area,” according to a report by the Honolulu Police Department’s Traffic Division.

Police said Honolulu Emergency Medical Services paramedics responded and took the girl in serious condition to a hospital but her condition later deteriorated and she was listed in critical condition.

She was not wearing a helmet at the time of the crash and speed appears to be a factor in this collision, police said, adding that it is unknown if drugs or alcohol were contributing factors.