Joe was rescued from the sewer system after a passer-by in the local area heard noises coming from a manhole cover early on Saturday morning and alerted the emergency services, the Oldenburg-Stadt Ammerland police department said.
Joe was found just 1,000 feet from his home address and taken to a nearby hospital where he was treated for hypothermia and dehydration.
The police said they didn't believe anyone else was involved in the incident.
Authorities found a 6 year-old girl missing since 2019 after receiving a tip different from any other information they had. An initial police report described Joe as having a learning disability. The search was ongoing, but they said he might misinterpret it as a game and hide it. Joe's surname hasn't been made public, in accordance with Germany's privacy laws. Immediately after the rescue, investigators began looking at the drainage system for clues to how he disappeared. The authorities concluded that Joe most likely climbed into a concrete drainage pipe while playing, and then crawled into the sewer system through a canal and got lost after several meters. A baby girl found in a drain in Mumbai discharged from hospital investigators said there are drainage manhole shafts and junctions at regular intervals where he was able to stand up, between the entrance to the drainage system and the place where Joe was found. Joe told police in an initial statement that he became increasingly disoriented while stuck in the sewers and was unable to find his way out. The police spokesman Stephan Klatte said he was so happy, according to CNN affiliate N-TV. That is absolute luck. There was a possibility that we wouldn't find the child there. Possibly - if he had not made a sound or these noises would not have been heard, then we may not have found him there at all, Klatte added.