A residential agency contracted to care for some of B.C.'s most vulnerable youth was shut down this year after a number of shocking allegations came to light, including that a staff member with gang ties offered cocaine to one of the kids.

The claims were made public Tuesday by Bernard Richard, the province's representative for children and youth, who said an investigation into the agency found only 10 of 33 staff and caregivers had received proper screening, including a criminal record check.

"The investigation resulted in nine of these employees – who had all been caring for children prior to the investigation – being barred permanently from further such work and 13 others being further screened due to concerning information," Richard said in a statement.

The staff member with alleged gang affiliations was also accused of smoking pot with the youth, according to Richard.

The closure forced officials to relocate 18 children and youth, a process the representative said is difficult and often re-traumatizing for youngsters who have already been through so much.

And while that agency closed, Richard said he has "grave concerns" about the way others still contracted by B.C.'s Ministry of Children and Family Development are being run.

He pointed to two other agency closures in recent years that displaced another 52 children and youth. Among them was 18-year-old Alex Gervais, whose tragic death created a scandal for B.C.’s children’s ministry and led to a number of recommendations from Richard's office.

Gervais was placed into a Fraser Valley hotel in what was supposed to be a temporary solution between homes, but leapt to his death in September 2015 after allegedly going 10 days without any contact with his caregiver.

In response to those recommendations, which were released in a report, Alex’s Story, in February 2017, the Ministry of Children and Family Development did implement a screening hub to help ensure staff members at contracted agencies are properly vetted.

But Richard said he's learned employees at 46 of 96 residential agencies still haven't been screened.

"The ministry has known about these issues for some time, has been presented with options to improve the system and yet continues to place the most vulnerable children in its care in harm’s way," said Richard, who outlined his latest concerns in a letter to minister Katrine Conroy.

Conroy responded Tuesday by promising to re-examine the cases of 800 children and youth currently placed in contracted residential agency homes in the province.

"I have asked the ministry to review each child’s circumstances, to determine the most appropriate placement to meet their needs," Conroy said in a statement. "I hope, and expect, this will result in moving some of those children and youth back to family-based foster homes."

The ministry will also create a new approval process that will be used to help determine where children and youth should be placed.

"Decisions must be based on the child’s particular needs, not on the simple availability of a bed. For example, a youth who is violent might need a resource with Plexiglas windows, and caregivers who are specifically trained to deal with violent behaviours," Conroy said.

The minister said the government has already been working to increase oversight of residential agencies, but admitted that "action hasn't been fast enough."