RUGAZI, Uganda (AP) _ Prisoners under armed guard today uncovered 40 bodies from a mass grave hidden at the edge of a sugarcane field, where authorities suspect more members of a doomsday Christian sect remain buried.

The discoveries in Rugazi come as authorities continued investigating the deaths of 490 other members of the Movement for the Restoration of the Ten Commandments of God elsewhere in the lush mountains of southwestern Uganda near the border with Rwanda and Congo.

The prisoners, with their shirts off and their pants rolled up, wrapped their noses in gauze and shared cigarettes to ward off the stench of rotting bodies, which drifted for hundreds of yards.

The prisoners, released for the day from a local jail, quickly unearthed the badly decomposed remains of 40 people, including at least two babies, and were continuing to dig this afternoon. Bodies buried together, or without coffins, are highly unusual in Africa, where funeral rituals are deeply important.

The Ugandan government, meanwhile, has set up a team of investigators to examine the contents of the grave, officials said.

The team, which includes chemists, a pathologist and forensic experts, was gathering in Kampala, Uganda's capital, and would be heading into the interior in the next day or so, Eric Naigambi, a police spokesman, said by telephone from Kampala.

After coming to Rugazi, the team will go to the village of Buhunga, where they will re-exhume 153 bodies of sect members that were found in two mass graves there, quickly examined by a local doctor, and reburied hours later.

Terenzi Kingera, a regional officer with Uganda's criminal investigation division, said the doctor had been ``overwhelmed'' by the job, so the corpses needed to be examined again.

He said the investigators main goal would be figuring out ``how could so many people be killed. Were they poisoned and with which kind of poison?''

The overall investigation has been plagued by logistical problems since it began. The Ugandan police is ill-trained and desperately ill-funded, often without vehicles or fuel to power them.

``The flow of funds from the Ministry of Finance has always been poor,'' Paul Bachengana, permanent secretary for the Ministry of Internal Affairs, said from Kampala.

A Ugandan legislator, meanwhile, has speculated that sect leaders orchestrated the deaths of their followers and then fled.

Senior Ugandan officials have quoted witnesses as saying the sect's two top leaders _ Cledonia Mwerinde, 40, and Joseph Kibweteere, 68 _ may have left the village of Kanungu on March 17, the same day a fire in a makeshift sect church there killed 330 members. Those reports are unconfirmed.

The deaths in Kanungu _ which set off the investigation _ were initially viewed as a mass suicide. However, officials, police and villagers have speculated that the two leaders fled as the sect grew increasingly divided when the world did not end Dec. 31 as was predicted, and that members may have wanted back their belongings, which they had surrendered on joining the sect.

Jim Muhezi, a member of parliament and a onetime head of Uganda's internal security agency, theorized Saturday that sect leaders cracked down viciously on the defiant, poisoning some, and urging the mass suicide to curb further defections.

Days after the Kanungu fire, the 153 bodies were found in Buhunga.

Police discovered the Rugazi grave Friday, when they came to inspect the compound that until recently belonged to Dominic Kataribabo, a defrocked priest and a sect leader. Kataribabo is believed to have died in the Kanungu fire.

The sect had up to 1,000 members, and authorities here fear most may have become victims. Government officials are treating Kibweteere as a fugitive and all the deaths as murder.