The family of a boy who vanished at the age of six in 2011 had their hopes dashed last night when it emerged a teenager, who claimed to be the missing child, was not telling the truth.

The youth claimed to be Timmothy Pitzen, whose disappearance from Aurora, Illinois, became a high-profile case. But the FBI said DNA tests showed he was not.

An FBI spokesman said: "DNA results have been returned indicating the person in question is not Timmothy Pitzen. A local investigation continues into this person's true identity."

He added: "To be clear, law enforcement has not, and will not, forget Timmothy, and we hope to one day reunite him with his family. Unfortunately, that day will not be today."

According to a police report, the teenage boy said he had been held captive by two “bodybuilder-type” men for years and escaped from a hotel where they were staying, running across a bridge as he fled.

The boy, wearing a red hooded top and green jacket, was found standing next to a road junction in Sharonville, a suburb of Cincinnati, 300 miles from Aurora, Illinois.

Witnesses said he had bruises on his face and seemed “very scared and agitated”. Police were called and he identified himself as Timmothy Pitzen.