An asteroid was spotted exploding over southwest China and Nasa says it was as powerful as 540 tonnes of TNT.

An asteroid has shot over the skies of China.

It came down near Shangri-la county in Yunnan.

Nasa later said the fireball was the equivalent to 540 tonnes of TNT, CCTV reported. It also had a seismic impact of 2.1 magnitude, CCTV said.