Moscow (CNN) -- Dozens of children and adults belonging to an Islamist sect in western Russia's Tatarstan region have been discovered living in an eight-level, underground bunker from which some had never left, authorities said Thursday.
"Upon receipt from the building, the children were in satisfactory condition," health worker Tatiana Moroz told CNN about the 27 minors. "The children were all fed, although they were dirty. Upon receiving them, we washed them. They have undergone a full examination -- all the Russian specialists have examined them, and taken all the analyses."
She added that laboratory test results on the children's health would be known Friday.
The state-run newspaper Russia Today said some were born underground and had never seen daylight.
Police say that more than 30 adults lived in the warren of rooms, where three people shared each square meter of living space, according to the state-run news agency RIA Novosti.
"The premises consists of cells without natural light and ventilation located in the basement and foundation and dug into the ground," said Irina Petrova, assistant to the state attorney. "It is an eight-level anthill."
At least 19 of the children, ages 1 to 17 years, were placed in institutional care while authorities determine whether to return them to their families; others were hospitalized for health checks.
Some of the children have no documents, RIA Novosti reported.
"A child involved in a sect becomes a hostage and his or her life is at risk," said Presidential Commissioner for Children's Rights Pavel Astakhov. "This violates nearly every one of the child's rights to health, education and normal development. Unfortunately, the victims' rehabilitation usually takes a long time and requires professional assistance. The parents will have to undergo the required treatment before they are allowed to visit their children."
The sect was literally unearthed August 1 in a suburb of the city of Kazan in Russia's mainly Muslim Tatarstan region during an investigation into militant groups.
Police detained some of its members, including its reclusive 83-year-old leader, Faizrakhman Satarov. Some of them are facing charges that include neglect of minors.
Russian media reports say Satarov's followers refused to recognize Russian laws or the authority of mainstream Muslim leaders in Tartastan.
RIA Novosti said members of the underground sect and their children had spent after nearly a decade living in tight quarters without heat, ventilation, sunlight or proper food.
The children had no access to health care or schooling and were discouraged from contacting outsiders, though sexual activity was encouraged, the agency said, adding that one of the children, a 17-year-old girl, was pregnant.
Satarov founded the sect in 1964, declaring himself a prophet and his house an independent Islamic state, Ria Novosti reported.
In 1966, he bought the property near Kazan, the region's capital, and built the bunker as a religious school, it said.
Almost 10 years ago, some 70 Satarov followers cloistered themselves inside and declared themselves an Islamic caliphate, it said.
Tatarstan police said that the house, built on 700 square meters, was built illegally and is subject to demolition.
"They have decided to eliminate our community, decided to wage war against Allah," sect member Gumer Ganiyev told Vesti TV. "They won't defeat Allah."
"This could just be some 83-year-old who wants to control people," said Shireen T. Hunter, a scholar on Islam and Russia who directs the Carnegie Project on Reformist Islam at Georgetown University and has visited the region several times.
"This may have nothing at all to do with radical or extreme Islam as we understand it. This man -- creating a caliphate? How is he going to do that? This just doesn't seem like the modus operandi of a serious radical cell bent on challenging the government."
CNN's Matthew Chance and Ashley Fantz contributed to this report