The crash happened at around 8:20 a.m. in Commack, on Harned Road near Donna Court, according to Suffolk County Police.
Investigators said Ilona Kaydanov and her brothers, ages 13 and 20, were jogging in a single file on the northbound shoulder of Harned Road when they were struck by a Chrysler Voyager.
Kaydanov was taken by ambulance to South Shore University Hospital in Bay Shore where she was pronounced dead, police said.
Her brothers were taken to Good Samaritan University Hospital in West Islip and treated for non-life-threatening injuries.
The driver of the Voyager, a 44-year-old Bay Shore woman, and her two adult passengers were not injured.
Detectives impounded her vehicle for a safety check. It was not immediately clear whether she will face charges.
Suffolk County Police are asking anyone who may have witnessed the crash to contact the agency at 631-854-8452.
This is a developing story. Check back to Daily Voice for updates.
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