Police launched an appeal for help Tuesday, more than a year after a boy's body was found in Germany's Danube River, weighed down with a flagstone slab and wrapped in foil. 

The body, believed to be that of a boy between 5 and 6 years old, was discovered on May 19 last year near Grossmehring in Bavaria, Germany, INTERPOL said. Officials still don't know who the young boy was and are working to uncover details of the suspicious circumstances surrounding his death. 

INTERPOL circulated a Black Notice, an international information-gathering alert, to the organization's 195 member countries. The notice included facial reconstruction images and physical characteristics of the boy. 

INTERPOL Secretary General Jürgen Stock called on the global law enforcement community to cross-check databases and consult open and unsolved cases. Investigators believe he likely spent time outside of Germany. 

"Someone, somewhere knows something about this boy, making it equally important to release certain details publicly," Stock said. "Whether he was the victim of trafficking, abduction or violence, we are committed to mobilizing all of INTERPOL's policing capabilities to identify him and help investigators shed light on his death."

The boy was approximately 3 feet, 7 inches tall and weighed around 33 pounds. He had brown hair and his blood type was O. The slab weighing down the boy's body was a "Natura Vigo" paving stone made by the German manufacturer Diephaus, according to INTERPOL.

Officials urged members of the public with relevant information to contact the national police team in Germany, especially if they know anything about a missing child whose characteristics and disappearance indicate a potential link to the boy found in the Danube. 

German police can work with INTERPOL to produce DNA comparisons for people who believe the boy could be a biological relative.

In:
• Missing Child

Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

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