DUBLIN, Va. (WUSA9) -- The search for Noah Terry Thomas of Pulaski County is now in a transitional phase and will continue overnight.
Police will soon only respond to specific investigation leads rather than covering as much ground as they can.
They are searching by foot, air and with K-9 units, considering everything from where others have gone missing in the past, to how much ground a five-year-old could typically cover by foot.
On Tuesday, police expanded the search area near the five-year-old's house in Dublin, Va. Officials with the FBI and dozens of volunteers are helping in the search, which has entered its third day.
So far, officials say the search has covered a four-mile radius of thick woods and open fields.
The Pulaski County Sheriff told members of the media on Tuesday morning that as more time passes, the search and concern intensifies for Noah Thomas.
Police are asking anyone who may have seen him or know where he is located to call the Pulaski Sheriff's Office.
Noah Thomas was last seen at 5461 Highland Road in Dublin, Va. Police believe that he left the house on foot.
The five-year-old is described as 4 feet tall and 60 pounds. He has green eyes and red hair. He was last seen wearing a camo jacket, black and yellow pants and Spiderman rain boots.
Many people have asked why Thomas' case did not prompt an Amber Alert. There are specific guidelines for an Amber Alert, including the confirmation that the child has been abducted, which police say this case did not meet.
If you know anything about the whereabouts of Noah Thomas, please contact the Pulaski Sheriff's Office at 540-980-7800 or the Virginia State Police at 1-800-822-4453, (1-800-VACHILD).