A lab in Trichy has concluded that the unidentified object that caused an explosion at a college in Vellore last week was a meteorite. A preliminary report by the National College Instrumentation Facility in Trichy said a scanning electron microscope study of the samples recovered from the site found that they were meteorite fragments.

The principal of the institute and a geologist, K Anbarasu said the samples contained carbonaceous chondrites, which are non-metallic meteorite parts containing mineral granules. He explained that it was not a common iron or stony meteorite and that further tests were needed for detailed answers. A senior space scientist at the Indian Space Research Organisation and two-time chairman of the Inter-Agency Space Debris Coordination Committee, V Adimurthy, said the findings may be “clinching evidence” and should be shared with other material science experts.

This discovery follows a statement from the National Aeronautics and Space Administration that the bus driver was not killed by a meteorite. Scientists at NASA said the photographs posted online of the dark-coloured stone recovered from the site looked like the result of a “land-based explosion”. Tamil Nadu Chief Minister J Jayalalithaa had earlier insisted that the explosion in which a bus driver died at an engineering college was caused by a meteorite.