Mexican authorities are still unraveling the horrors allegedly committed on nearly 500 children sheltered at "La Gran Familia" refuge in the southwestern state of Michoacan.

At The Big Family shelter, scores of children - some as young as two months old - were denied visits from their parents, virtually imprisoned in vermin-infested quarters and routinely subjected to physical, psychological and sexual abuse, authorities said.

Authorities raided the sprawling, squalid shelter in the city of Zamora Tuesday after a number of parents complained about being denied access to their children, Mexican Attorney General Jesus Murillo Karan told reporters.

"We found close to 500 children in truly deplorable conditions," Murillo said.

Victims told investigators that children were routinely forced to beg for money on the streets, eat unsanitary food and sleep on hard floors crawling with rats and roaches, Murillo said. It was not clear from Mexican authorities how so many children - along with some adults - came to be at the shelter.

The operator of the shelter, Rosa del Carmen Verduzco, was detained along with eight of her employees, authorities said. They were being questioned in connection with abuse and other charges.

"This is truly upsetting," Michoacan governor Salvador Jara Guerrero told reporters. "We did not expect to find such conditions... We must not allow these things to occur - not in Michoacan, not in the republic."

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