HEART-STOPPING footage has emerged depicting two young boys playing on a narrow building ledge some 30 storeys high in China.

The pair were spotted by a neighbour in a nearby apartment block in Lanzhou City.

In the footage, the boys can be seen carelessly walking around the edge of a building, chatting to one another and apparently oblivious to the fact that one small slip would result in tragedy.

“We were absolutely horrified,” says a woman in the video, who’s understood to be the property security manager.

“Thank goodness the boys are not injured.”

It’s not clear where the kids’ parents were at the time of the daring stunt