A witness helped police track down a hit-and-run driver who allegedly struck and killed an 85-year-old Norcross man Sunday evening, authorities said.

Kanaiyalal P. Patel was walking across Kings Ridge Drive at Singleton Road shortly after 6 p.m. Sunday when he was hit by a 1999 Ford F-150 pickup truck that was turning from Kings Ridge onto Singleton, Gwinnett police Cpl. Edwin Ritter said.

"A witness stated that the vehicle did not stop for the stop sign on Kings Ridge Drive and struck the pedestrian as he crossed the roadway," Ritter said. "The driver of the vehicle did not stop and drove off."

Patel was taken to Gwinnett Medical Center, where he later died.

Ritter said a witness followed the pickup to the Oakbrooke Pointe Apartments in Norcross.

"Officers located the driver with the assistance of the witness and took her into custody," he said.

Ruth Escobar, 50, of Norcross, was booked into the Gwinnett County Jail, charged with vehicular homicide, hit-and-run, failure to obey stop sign and driving without a valid license.