DANVILLE, Va. -- An Amber Alert was issued Monday morning for a missing Virginia girl who authorities believe is in extreme danger after being abducted by a registered sex offender after he assaulted her mother.Danville police are searching for 7-month-old Emma Grace Kennedy.She is about 2 feet 2 inches tall, weighs 18 pounds, has blonde hair, blue eyes and has a small scar on her left cheek.Emma was last seen wearing a light blue onesie with dots and a white rabbit on the left leg and matching headband.Police believe her abductor is 51-year-old Carl Kennedy, who is a registered sex offender in North Carolina. He is described as 5 feet 8 inches tall, weighs 170, has gray hair, green eyes, a left ear piercing and tattoos on both arms, consisting of skulls, an eye, pitbull and a wizard.Kennedy was last seen wearing a brown T-shirt, gray shorts and black and white Skechers shoes.Police said Kennedy abducted the child after assaulting her mother at a Kwik Stop on Riverside Drive in Danville, Virginia.Authorities said the two were last seen leaving the gas station and could be headed to North Carolina. They may be in a gold Suzuki with North Carolina license number EKZ-5093.The vehicle also has a Johnny's Auto Sales emblem on the trunk.Officers believe Kennedy is armed with a knife. Authorities did not release the nature of their relationship.Those with any information are asked to call the Danville Police Department at (434) 799-6510 or 911.