LIMA, Peru —  The sophisticated design and colorful artwork found in a 4,000-year-old temple unearthed near Peru's northern desert coast suggests that early civilization here was more complex than originally thought, archaeologists said.

Ventarron, a 7,000-square-foot site — a bit larger than a basketball court — with painted walls and a white-and-red mural of a deer hunt, points to an "advanced civilization," said the lead archaeologist who excavated the site last week.

"We have the use of a construction material that is not primitive," Walter Alva, a prominent Peruvian archaeologist who headed the government-funded dig, said of the temple's mud bricks, which were made from local river sediments instead of rocks.

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The pre-Incan structure's "harmonious" design is typical of later temples and demonstrates remarkable precision: it points due north, Alva said told The Associated Press by telephone.

Alva, who led one of Peru's most famous archaeological digs uncovering the Moche Lords of Sipan tombs in the late 1980s, said results from carbon dating conducted in the U.S. show that the Ventarron temple was constructed 4,000 years ago.

Fragments of paint found on the walls and an almost completely intact inner mural show the civilization had "the concept of decoration," Alva said.

"This discovery once again supports the rising of complexity early in Peru," said Kit Nelson, a Tulane University archaeology professor who specializes in early desert-dwelling cultures. The find "provides new early dates for the decorating of public architecture and the use of adobe bricks."

Robert Benfer, an archaeologist based at the University of Missouri-Columbia who has studied early Peruvian civilization for more than 30 years, said that many early temples were painted and had murals, but that most were not preserved.

"We're beginning to think they're more common than we used to think. It's all the luck of preservation," Benfer said in a telephone interview with the AP.

Alva said bones of Amazonian parrots and monkeys were found on the site, 405 miles north of the capital, Lima, indicating that Ventarron's society traded with counterparts in Peru's distant jungle.

The oldest known city in the Americas is Caral, also near the Peruvian coast, which researchers date to 2627 B.C.