The driver who struck and seriously injured a pedestrian Thursday in Gwinnett County drove across the center line, police said Friday.

Tiffany Hayes, 31, of Snellville, was driving westbound on Bethany Church Road near Brannan Road with a 7-year-old boy in the back, police spokeswoman Cpl. Michele Pihera said.

Georgette Stovall, 51, of Snellville, was walking her dog on the sidewalk on the other side of the road. Hayes’ car hit both Stovall and her dog, Ali, Pihera said.

Stovall was taken to Gwinnett Medical Center in Lawrenceville, Pihera said. Her dog is still missing.

Pihera said Hayes’ actions do not appear intentional. Hayes’ car, a 2009 Honda CRV, was taken to police headquarters for an inspection.

Anyone with knowledge of the dog’s whereabouts can call police at 770-513-5700.