According to Egyptian antiquities officials, an international team of architects and scientists have observed "thermal anomalies" in the pyramids of Giza.

BBC reports that, thermal cameras detected higher temperatures in three adjacent stones at the bottom of the Great Pyramid.

Officials said possible causes included the existence of empty areas inside the pyramid, internal air currents, or the use of different building materials.

It comes as experts search for hidden chambers within the pyramids.

The tombs of the pharaohs Khufu (Kheops), Khafre (Khephren) and Menkaure (Mycerinus) were built in the Fourth Dynasty, about 2613-2494BC.