Pacing back and forth across the Giza plateau, Mamdouh El-Damaty, Egypt’s beleaguered minister of antiquities, could scarcely keep a smile from his face as he broke the news of a potentially ground-breaking discovery.

An international team of archaeologists and engineers has identified an “impressive anomaly” at the base of the Great Pyramid of Khufu, also called Cheops, Giza’s largest pyramid.

Temperature differences between stone blocks indicate that there may be hidden chambers or clues to the pyramid’s construction inside. (In recent weeks similar scanning by other researchers in the tomb of King Tut revealed the possibility of a hidden chamber as well.)

“The pyramids have lots of secrets,” Damaty said against a backdrop of enthusiastic applause and the flash of cameras.