CAIRO — Egypt says it has discovered a number of ancient burial chambers containing some 40 mummies in the desert province of Minya, south of Cairo.

Officials told reporters on Saturday at the site that the chambers, which were cut out of rock, belonged to a middle-class family who probably lived during the Ptolemaic, early Roman or Byzantine period. The Ptolemaic period lasted from 305 to 30 B.C.

The mummies are in good condition and at least 10 are of children. Some were decorated with “demotic handwriting” — a form of ancient Egyptian script used by ordinary people. Pottery, papyri and colorful mummy cases were also unearthed.

Egypt has made a series of archaeological finds recently, and it has been heavily promoting them to revive its tourism industry, a staple of its economy that was decimated by the chaos that followed its 2011 uprising.