A Mayan carving at the El Zotz archaeological site in Northern Guatemala

Archeologists in Guatemala have discovered a Mayan king's tomb packed with a well-preserved hoard of carvings, ceramics and children's bones that cast fresh light on the vanished civilization.

Researchers uncovered the burial chamber dating from 300 - 600 AD beneath the El Diablo pyramid in the city of El Zotz in the jungle-covered Peten region in May, but the discovery was only made public on Thursday.

The well-sealed tomb -- measuring 10 feetl, by nearly 4 feet wide wide and 5 feet deep -- helped preserve textiles, wood carvings and red and yellow ceramics decorated with fish and wild boar motifs, researchers said.

"It's like their Fort Knox, their depositary of wealth with textiles and ... trade items and that's what's overwhelming about it," said Stephen Houston, the dig's director at El Zotz, who is based at Brown University in the United States.

The Central American nation is dotted with pyramids and ruins from the ancient Mayan civilization, which reached a high point between 250 and 900 AD and covered territory from modern day Honduras to central Mexico.

Archeologists said the dig at El Zotz, which means "bat" in several Mayan languages, has provided fresh insights into the civilization's funeral rites.

Adolescents were frequently sacrificed during the burial of Mayan kings. But in an unusual discovery, archeologists excavating at El Zotz uncovered bones belonging to children as young as 12 months old.

The dig also revealed evidence that the king was buried in a traditional dancer's costume, adorned with conch shells and slivers of jade, which is believed to be a first.

El Zotz is near the larger forest-wreathed ruins at Tikal, which are a popular destination for U.S. tourists.

Historians say El Zotz was often caught in the middle of battles between Tikal and Calakmul, which lies to the north in modern day Mexico.

Like many archeological sites in Guatemala's remote Peten region, El Zotz is at risk from looters, poachers and loggers trying to make a living out of the forest, as well as drug traffickers seeking to move cocaine into Mexico.