Archaeologists working in an Egyptian oasis have found a necropolis containing dozens of brightly painted mummies dating back as far as 4,000 years, the country's antiquities chief said on Sunday.

"The mission found dozens of mummies in 53 rock-hewn tombs dating to the Middle Kingdom" from 2061-1786 BC, Zahi Hawass told AFP.

"Four of the mummies date back to the 22nd Dynasty (931 to 725 BC) and are considered some of the most beautiful mummies found," he said.

The linen-wrapped mummies are painted in the still-bright traditional ancient Egyptian colours of turquoise, terracotta and gold. The team also found 15 painted masks, along with amulets and clay pots, Hawass said.