NASA on Wednesday said it was unlikely a meteorite was responsible for killing a man at a college campus in India last week, as local scientists continued to examine the mysterious object recovered from the scene.

Authorities in southern Tamil Nadu state had claimed that a meteorite fatally struck a bus driver and injured three others on Saturday.

After reviewing photographic evidence, the US space agency told AFP that they did not believe the object was a meteorite.

"While more details are forthcoming from local scientists, this is unlikely something from space," Dwayne Brown, a NASA spokesman, said in a statement.

"To form a crater the size of what has been posted online would have required a meteorite of at least several kilograms," he said.

Local officials recovered a blue object, which was roughly smaller than an adult hand, near the accident site and claimed it had left a crater in the ground. The college also reported that buildings on the campus were damaged during the incident.

Two days after the episode, Tamil Nadu Chief Minister Jayalalithaa Jayaram said the unknown object was a meteorite, triggering an international debate.

G.C. Anupama of the Indian Institute of Astrophysics, which sent a team to examine the object, said the group has not finished their investigation yet.

"The team has received a sample from the local police investigating the event. The nature of the object will be ascertained only after a detailed analyses by the experts," Anupama, the dean of the institute, told AFP.

Meteors are particles of dust and rock that usually burn up as they pass through Earth's atmosphere.

Those that do not burn up completely, surviving the fall to Earth, are known as meteorites.

In February 2013 a meteorite plunged over Russia's Ural Mountains, creating a shockwave that injured 1,200 people and damaged thousands of homes.