Through a partially opened underground door, Egyptian authorities gave a peek Friday into the first new tomb uncovered in the Valley of the Kings since that of King Tutankhamun in 1922. U.S. archaeologists said they discovered the tomb by accident while working on a nearby site.

The tomb, which has five wooden sarcophagi with painted funeral masks, probably contains members of an 18th Dynasty pharaoh's court, Edwin Brock, co-director of the University of Memphis excavating team, told The Associated Press.

So far, archaeologists have not entered the tomb, having only opened part of its four-foot-high door last week. But they have peered inside the single chamber to see the sarcophagi, believed to contain mummies, surrounded by around 20 pharaonic jars.

"It was a wonderful thing. It was just so amazing to find an intact tomb here after all the work that's been done before. This was totally unexpected," Brock said.

"I don't think it's a royal tomb, maybe members of the court," he said. "Contemporaries of Tutankahmun are possible — or of Amunhotep III or even Horemheb," he said.

Based on their style, the jars appear to date to the late 18th Dynasty.

On Friday, Egyptian antiquities authorities allowed journalists a first look into the tomb through the opening in the door, located at the bottom of a 30-foot shaft.

It is near the tomb of Tutankhamun — the last new burial site discovered in the valley, in 1922 by British archaeologist Howard Carter.

The discovery has broken the long-held belief that there's nothing left to dig up in the Valley of the Kings, the desert region near the southern city of Luxor used as a burial ground for pharoahs, queens and nobles in the 1500 BC-1000 BC New Kingdom.

The 18th Dynasty lasted from around 1500-1300 BC and included the famed King Tut.

Photos issued by Egypt's Supreme Council of Antiquities showed the interior of the tomb — the bare stone walls undecorated — with at least five sarcophagi of blackened wood amid white jars, some apparently broken.

The coffins appear to have some damage from termites, Brock said.

"It's going to take a lot of conservation work to consolidate these things before we can take them out," he said.

The team, led by Otto Schaden, will continue its excavations of the site for the remaining five months of the dig season, he said, though he did not say when they would completely open the door so archaeologists can go inside.

"We're going to be very meticulous in our excavations," he said.

The archaeologists were working last year on the neighboring tomb of Amenmeses, a late 19th Dynasty pharaoh, when they found the remains of ancient workmen's huts. They then discovered a depression in the bedrock that they suspected was a shaft.

When they returned to work during this excavation season, they opened the shaft and found the door, which was opened last week, Brock said.

Since the discovery of Tut's tomb, experts believed that the Valley of the Kings contained only the 62 previously known tombs — labeled KV1-KV62 by archaeologists.

"I wouldn't be surprised if we discover more tombs in the next 10 years," American archaeologist Kent Weeks told AP.

Weeks made the last major discovery in the valley. In 1995, he opened a previously known tomb — KV5 — and found it was far larger than expected: more than 120 chambers, which he determined were meant for sons of the pharaoh Ramses II.

"It's ironic. A century ago, people said, 'The Valley of the Kings is exhausted, there's nothing left,'" he said. "Suddenly Carter found Tutankhamun. So then they said, 'Now there's nothing to find.' Then we found KV5. Now we have KV63."

Weeks, who was not involved in the new discovery but saw photos of the tomb's interior, said it was probably built for one person, but that multiple sarcophagi were moved in later for storage. The jars, he said, appear to be meat jars for food offerings.

Objects in the tomb "could be 200 to 400 years later than the original cutting of the tomb," he said.