A woman’s vehicle was taken at knife point in the Tysons Corner area Saturday after she offered a ride to another woman who approached her in a store parking lot and claimed to be out of gas, Fairfax County police said.

Police said the victim, a 59-year-old Fairfax resident, was approached about 1:30 p.m. in the parking lot of the Neiman Marcus store at Tysons Galleria.

The thief, who described herself as a student, said she needed a ride to a gas station, police said.

The victim invited the thief into her 2003 Acura and headed toward Route 123, but during the drive, the thief displayed a knife and ordered the driver out. The driver was left at Route 123 and Old Courthouse Road.about a half-mile west of the shopping center. She was not injured.

Police said the vehicle had not been found.

The thief was described as white, between 20 and 25 years old, with medium-length brown hair and blue eyes. She was about 5-foot-8 and wore a black hooded sweatshirt and light-colored pants, police said.