The inside of a Mayan tomb thought to be 1,500 years old has been filmed by archaeologists.
Using a tiny video camera, the researchers were able to capture images of the burial chamber in Palenque in south-eastern Mexico.
As the device was lowered 16ft (5m) down into the tomb, they saw red paint and black figures emblazoned on its walls.
The scientists say the images will shed new light on the Mayan civilisation.
The tomb in Palenque was discovered in 1999 and then filmed using a tiny camera lowered on a pole, but archaeologists have not been able to excavate for fear of undermining the pyramid.
Palenque was a Mayan city-state in what is now Mexico's Chiapas state, but after its decline during the 8th Century AD it was absorbed into the jungle.
It has been extensively excavated, in particular over the past two decades, but much of it remains to be uncovered.
Mexico's National Institute of Anthropology and History (Inah) said its archaeologists had been aware of the tomb for more than a decade, but had not been able to examine it.
"Its difficult location and the work to consolidate the plinth had until now impeded penetration into the enclosure, which jealously guards the remains of a very important person from this ancient Mayan city," Inah said in a statement.
It said that the researchers overcame the difficulties by lowering the remote-controlled camera the size of a matchbox down along a narrow shaft into the largely intact chamber.
Inside, the camera revealed nine black figures painted on blood-red walls, along with jade and shell fragments, which are believed to be part of a funerary costume.
But unlike in other tombs in Palenque, no sarcophagus has been found. "It is very probable that the fragmented bones are lying directly on the stones of the floor," Inah said.
Experts say the tomb probably dates to between AD431 and 550, and could belong to the first ruler of Palenque - K'uk Bahlam I.
Another theory is that it could even belong to Ix Yohl Ik'nal, the city's early female ruler.
Archaeologist Martha Cuevas said the tomb's proximity to other burial sites suggested it may be part of a royal necropolis.
Correction 28 June 2011: To make it clear it is not the first time the tomb has been filmed.