MOSCOW, Russia (CNN) — Priests have tried unsuccessfully to persuade members of a doomsday cult to leave a cave in southern Russia where they remain barricaded inside despite the intervention of their leader.

The cult members — including four children — holed themselves up in a ravine in the Penza region, about 640 kilometers (400 miles) southeast of Moscow, earlier this month, threatening mass suicide if the authorities try to intervene, a government official said.

On Thursday, Russian Orthodox monks tried to contact the cult, The Associated Press reported, but members refused to speak to them. Priests went again Sunday, but the followers refused to listen to their arguments, a security official added.

The 29 members of the cult, which calls itself the "True Russian Orthodox Church," say they will ignite gasoline canisters if authorities try to force them out, regional administration spokesman Yevgeny Guseynov told CNN.

Guseynov said officials would try to find experienced negotiators. "There is no talk whatsoever of any sort of storming the site" , he said.

The cave dwellers are also refusing to speak to Russian Orthodox priests brought in to negotiate, he said.

Kuznetsov was charged Thursday with setting up a religious organization associated with violence. He has been undergoing psychiatric exams since his arrest.

"I’ve met the man, and he’s definitely mentally sick, big time," Guseynov told CNN.

A trained engineer, Kuznetsov did not let his followers watch television, listen to the radio or handle money, according to Russian media reports.

Among the children inside the cave is an 18-month-old baby, reported Itar-Tass, the Russian news agency. Temperatures in the cave are below 12 degrees Celsius (54 degrees Fahrenheit), the Russian news agency reported.

The cult members have gathered enough food supplies to last until spring, according to the agency.

A 24-hour operation has been established in the nearby village of Nikolskoye incorporating teams of local police, officers from the Russian Ministry for Emergency Situations and medical staff.

Guseinov said specially trained negotiators have arrived on the scene to talk with the cult members.

The negotiators are trying to persuade them to accept food, medicine and hot water to bathe the children, he said.