An 8-year-old boy from the northwestern German city of Oldenburg was found in a sewer after he went missing for eight days, police said Tuesday.

The Ammerland police department said in a statement that the boy, identified as “Joe,” went missing on June 17. The boy's identity has been kept private due to Germany privacy laws.

He was discovered Saturday by a pedestrian who passed the sewer and heard him make “noises.” The boy was located about 1,000 feet away from his home.

"Thanks to a tip from the public, we were able to find Joe in a sewer system," police chief Johann Kuhme said.

"The most important thing is that he is alive and was immediately taken to a hospital where he is in good hands. We can all breathe a sigh of relief," Kuhme said.

Police spokesperson Stephan Klatte called it "luck" that a person who heard the boy in the sewer is what helped them find him after more than a week.

"That is absolute luck. Of course, 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. We are so happy -- truly," Klatte said.

The boy was taken to the hospital on Saturday for hypothermia and dehydration. It was explained in his initial missing persons report that he has a learning disability that could have made him think it was a game to be hiding for so long.

Investigators believe the boy may have climbed into a drainage pipe then crawled further into the sewer system and got lost.