A veteran teacher of the Grove City Area School District gifted program died instantly Friday when the car she was driving collided with a school bus at about 7 a.m. on state Route 258, a half mile south of Jervis Road, state police said.

Linda M. Krafft, 45, of Slippery Rock was pronounced dead at the scene by Mercer County Deputy Coroner Dr. David Hoyt, after her car rear-ended a Grove City school bus, police said.

The bus driver -- Lisa J. Montanile, 34, of Grove City -- and 10 students on the bus were not injured, police said.

Police blamed operator error for the crash.

According to trooper Charles M. Turik Jr., a witness driving behind Mrs. Krafft's car said he was going about 45 mph and that her car was going a bit faster.

The bus was moving only about 20 to 25 mph, police said. The accident occurred about 3 or 4 miles from the school, police added.

According to Superintendent Dr. Robert Post, Mrs. Krafft had taken a sick day Friday.

Mrs. Krafft, who was with the district 15 years, taught about 60 students in three district schools: Hillview Intermediate Center, Highland Elementary School and Grove City Middle School.