Lahun, Egypt - Archaeologists have unearthed a cache of pharaonic-era mummies in brightly painted wooden coffins near Egypt's little-known Lahun pyramid, the site head said on Sunday.

The mummies were the first to be found in the sand-covered desert rock surrounding the mud-brick Lahun pyramid, believed to be built by the 12th dynasty pharaoh Senusret II, who ruled 4,000 years ago. The team expects to announce more finds soon.

The site was first excavated more than a century ago.

"The tombs were cut on the rock itself, and they vary in architectural designs," said archaeologist Abdul Rahman Al-Ayedi, head of excavations at the site. "Most of the mummies we discovered were with these bright and beautiful colors."

At the site, bare skulls from some of the mummies sit on a hillside while workers gently brush away sand from coffins below the earth that bear images of their occupants, some painted in striking hues of green, red and white.

Ayedi said the dozens of tombs dotting the site near Fayoum, 60 km (35 miles) south of Cairo, could give insight into the development of Egyptian funerary architecture and traditions from the Middle Pharaonic Kingdom all the way to the Roman era.

Some of the tombs were built on top of graves from earlier eras, and Ayedi said archaeologists had found dozens of mummies, including around 30 that were well-preserved. Some were inscribed with prayers intended to help the deceased.

SITE MAY DATE TO EARLIER ERA

Ayedi said Egypt would soon announce an additional significant find near the Lahun pyramid, once covered by slabs of white limestone, showing the site could date back to an earlier era thousands of years before previously thought.

"The prevailing idea was that this site has been established by Senusret II, the fourth king of the 12th dynasty. But in light of our discovery, I think we are going to change this theory, and soon we will announce another discovery," he told reporters.

He said teams had made a discovery dating to before the 12th dynasty, but gave no details on what it was and said an official announcement could be made within days.

Ayedi said he had wanted to excavate at Lahun, Egypt's southernmost pyramid, because he was not satisfied with the result of the first excavation there in the 19th century, saying it did not match the significance of the site.

"The size of the site is huge. So I thought that we could unearth a lot of elements in this site. At the beginning of the excavation, I thought that we may rewrite the history of the area, and I was right," he said.

Archaeologists found the main entrance to the pyramid last year in a 16-meter well, and later found storage jars and other objects inside before finding the mummies in the surrounding desert stone in recent months, Ayedi said.

Egypt, whose economy relies heavily on tourism, has made several significant discoveries this year including a rare intact mummy found in February in a sealed sarcophagus near the world's oldest standing step pyramid at Saqqara, near Cairo.

Archaeologists hope to start digging soon in search of the tomb of Cleopatra and possibly her lover Mark Antony on Egypt's north coast. Cleopatra, facing possible captivity in Rome, is alleged to have killed herself by the sting of an asp in 30 BC.