Members of the activist organization, which established a chapter in Winnipeg earlier this year, say they are taking matters into their own hands with regards to missing and murdered aboriginal women.
The chapter announced Thursday that it has set up a task force investigating the high-profile disappearances of five indigenous women: Tanya Nepinak, Sunshine Wood, Claudette Osborne, Mildred Flett and Jennifer Catcheway.
Lamb was charged last year with three counts of second-degree murder in the deaths of Nepinak, 31, along with Carolyn Sinclair, 25, and Lorna Blacksmith, 18.
Lamb remains in custody. The allegations against him have not been proven in court.
AIM member Morris St. Croix said he met with Lamb last week in an attempt to get more information about Nepinak, whose remains have not been found.
"When I went in there, what he tried to do is try to plead his innocence to me, and I just didn't buy it," St. Croix said of Lamb.
Winnipeg police would not comment on AIM's probe, except to say anyone with tips regarding a homicide should contact police investigators who are trained to handle such matters.
However, St. Croix said the police are not doing enough in their investigation.
"They want to do their own thing. That's all right, I'm going to do my own thing. I don't need permission to do this," he said.
Sue Caribou, an aunt of Nepinak, said she's glad someone else is stepping forward to help because she believes police haven't done enough to locate Nepinak's remains.
Investigators did conduct a search for Nepinak's remains at the Brady Road landfill last year, but their six-day search uncovered no evidence.