A Canadian army captain, who once led a team of military trainers in Afghanistan, now faces 22 criminal charges at home.

Capt. Malcolm Grace, a staff officer and planner with the Canadian Manoeuvre Training Centre based at CFB Wainwright, was transferred to Edmonton when criminal charges were laid against him in February 2016, said Capt. Graham Kallos, public affairs officer.

"He is restricted in what he's doing and he is being monitored by the chain of command where he is," Kallos said. "He is still involved with helping train, but remotely."

Because of the sexual nature of some of the charges that have been laid, a publication ban has been imposed on the identity of the woman who was allegedly victimized repeatedly by Grace over the course of seven years.

CBC News has learned a two-day preliminary hearing is scheduled to begin Thursday in Wainwright, Alta.

Grace, 45, is accused of repeatedly assaulting and sexually assaulting the woman, who was not a member of the military. Information filed with the courts alleges Grace unlawfully confined the woman "at least" twice and sexually assaulted her at gun point and with a knife.

Grace is also accused of twice trying to strangle the woman and issuing death threats against her; assaulting the woman's children, who were teenagers at the time; and threatening to hurt or kill a male military captain.

RCMP investigation began in February

Cpl. Denice Rogan, with Wainwright RCMP, said its investigation began in February when the woman came forward to complain about Grace.

Rogan said the investigation is ongoing.

Rogan called the case "fairly shocking," citing the disturbing allegation of weapons that were used during sexual assaults. She said Mounties deliberately chose not to make the charges public when they were laid in February.

"In discussion with several people, we decided not to," she said. Rogan declined to identify who the RCMP had discussions with to reach that decision.

CBC learned of the charges against Grace through a tip from a member of the public.

Grace is free on bail, but is not allowed to have any contact with the woman or her children.