Published reports say a 17-year-old girl and her infant daughter — both members of Lev Tahor —were met by police Sunday afternoon and will be returned to Ontario at an unspecified time.
Calgary police would only tell The Canadian Press they had assisted in the apprehension of two people for Chatham-Kent Children's Services.
The children's aid agency could not be reached for comment Sunday.
At least two Lev Tahor families left Canada for Guatemala last week amid child custody proceedings, but some of them were stopped in Trinidad.
Nine of them were brought back to Canada late Saturday, including six children who were then placed in the care of the Children's Aid Society.
Peel Police Sgt. Dave Housdon said the three adults were being processed by the Canada Border Services Agency.
A spokeswoman for the agency said CBSA "continues to work closely with local law enforcement agencies on this case," but wouldn't say whether the three had been released.
The families had filed an appeal in Trinidad against the decision denying them entry but it was rejected because it was made outside the allowable time frame, the country's attorney general, Anand Ramlogan, said Sunday.
He said that decision came after he advised immigration officials on the statutory time limits for appeals.
Early last week, an Ontario judge issued an emergency order that 14 Lev Tahor children be placed in the care of children's aid but police said Thursday that most of the children had left the country.
About 200 members of the sect — 114 of them children — settled in Chatham, Ont., last year after suddenly uprooting from Ste-Agathe-des-Monts, Que.
Child-welfare authorities in Quebec spent a year investigating issues related to hygiene, health, and allegations that the children weren't learning according to the provincial curriculum.
Late last year, a Quebec court ordered that 14 Lev Tahor children be placed in foster care.
The group has denied all allegations of mistreatment.