LONDON, ON - Days after a boy was severely beaten and an employee charged with attempted murder, details are emerging about the provincial facility that treats children with mental-health problems.

Information about the Child and Parent Resource Institute (CPRI) comes from the Ministry of Children and Youth Services that funds the facility in London, ON.

CPRI takes in children from birth to age 18 from 17 counties in Southwestern Ontario. It has six highly specialized residential treatment units for children with complex needs, including mental-health issues, behavioural disturbances and developmental challenges.

Each residential unit houses between eight and 10 children.

It was from one of these residential units that a 12-year-old boy was taken Sunday night.

Staff became concerned for his welfare and called police just before midnight. The boy was found in the woods behind the unit, suffering from "severe trauma" after a beating.

A developmental service worker on contract with CPRI, Greg Simard, 24, faces several charges, including attempted murder.

Although all staff with direct contact with clients must undergo a police check, there isn't any psychological testing of staff, ministry officials said.

But, according to the ministry, the clinic has many security features.

The facility has an internal complaint and review procedure if a client or parents of a client have problems with a staff member.

There is at least one staff member in each residence during the night. Exterior doors to the residential units are locked at night. Children's bedrooms are locked from the inside and staff have keys to the client doors.

Bedroom doors are alarmed, and staff carry portable communication devices. A senior officer in charge completes regular rounds in all the units, and there's an emergency response code system in place.

Given the stringent security in the residential units, questions remain: How was a 12-year-old boy removed from the locked residential unit? How long did it take staff to figure out that the boy and a worker were missing?

A spokesperson for the ministry said it's co-operating with the police investigation and will conduct its own probe.

The 12-year-old boy remains in critical condition in hospital.

Simard is charged with attempted murder, forcible confinement, uttering threats and assaulting a police officer.

He also faces a charge of committing an indecent act that isn't related to the CPRI charges.

Simard is set to appear in court by video on Thursday.