Investigators say it happened just after noon on Friday on Anasazi Indian Way in Highlands Ranch.
Deputies say the parents left the car running when they went to the garage sale and that is when Robert C. Orr of Littleton got in and drove away. The children are 1 and 3 years old.
He was found a short time later near Highlands Ranch Parkway and Broadway. The children were not hurt and were taken back to their parents.
Deputies are calling the incident a "stranger abduction" and Orr faces charges of second-degree kidnapping, child abuse, motor vehicle theft and first-degree criminal trespassing.
Authorities say this is a reminder that parents should be cautions and not leave their children unattended in a car.
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