Authorities in Kerala said on Saturday that no natural earthquake has been recorded in Wayanad, but experts warned that "subsurface acoustic vibrations" due to landslides may be causing the rumble heard in the area.

The National Centre for Seismology (NCS) said in a statement that it has received reports of "felt tremor" and "rumbling sound" in Wayanad and its adjoining areas.

"The Ministry's National Centre for Seismology (NCS) said that the felt tremor reported by media sources, accompanied by a rumbling sound, may be due to the shifting of unstable rock masses accumulated during landslides from one level to a lower level for better stabilization," it said.

The NCS further explained that this process may have generated subterranean acoustic vibrations due to frictional energy. "The NCS further explained that this energy has the potential to propagate up to hundreds of kilometers through subsurface cracks and fractures associated with subterranean lineaments, which may have caused rumbling sounds and ground vibrations in the area as a natural phenomenon in landslide-prone zones," it said.