Two "bizarre objects" that apparently fell from space were found in two locations in northern Vietnam on Saturday morning.
At about 6 a.m., an orb fell out of the sky on to remote land in Tuyen Quang Province.
"The sky was clear, suddenly we heard a thunder-like noise," a witness told Thanh Nien. Locals people later found the orb near a stream.
The strange object is found near a stream
The spherical object measures about 80 centimeters (31.5 inches) in diameter, apparently made of some metal alloy, the witness said.
Around the same time, another metal-like ball hit a garden in Yen Bai Province, right next to Tuyen Quang, also after a thunder-like noise.
Ta Duy Chinh, a local military official, said the object measures about 27 centimeters (10.6 inches).
Another sphere was found in a garden in Yen Bai Province
The army have cordoned off both areas in Tuyen Quang and Yen Bai for investigation.
Authorities remained baffled, but they concluded that neither of the spheres were an explosive device.
Several similar "bizarre spheres" dropped in Africa, Australia, Latin America and Europe in the past 20 years. Last October four "mysterious metal balls" were discovered in Spain and Turkey.
A commentator on tech site Gawker in 2011 identified such a ball as a piece of an unmanned rocket.
"For anyone wondering what it actually is, it's likely a ... hydrazine bladder tank ... They're used on unmanned rockets for satellite launches," the commentator said.
A metal sphere that dropped out of the sky and hit Australia in 2011. Photo: AFP
According to NASA, more than 500,000 pieces of space debris are orbiting Earth, with bits of space junk falling to Earth every year.