Scientists have released the first X-ray images of a mysterious spherical object found in Colombia that locals claim is of alien origin. The so-called “UFO” was spotted in March over the town of Buga, zigzagging across the sky in a pattern that defies description of conventional aircraft. The object was discovered shortly after landing and has since been analysed by scientists, who have found it to be made up of three layers of metal-like material and 18 microspheres surrounding a central core they call a “chip”, the Daily Mail reports.

Radiologist Dr. Jose Luis Velasquez, who examined the sphere, said he found “no welds or joints” that would normally indicate man-made construction. He and his team concluded: “This is a man-made object, as it shows no signs of welding and its internal structure is composed of high-density elements. Further testing is needed to establish its origin.”

The sphere also features symbols that the team compared to ancient scripts, including runes, the Celtic ogham script and Mesopotamian writing, the Daily Mail reports.