A former common-law partner has been arrested and charged with first-degree murder in the death of a Peterborough, Ont., woman.

Robert McGregor of Smith-Ennismore-Lakefield Township was arrested and charged Thursday. He also faces a charge of obstructing police.

Peterborough Lakefield Community Police Service said they launched a missing person investigation after Joanne MacKenzie, 23, went missing last Saturday.

With the public’s help and the assistance of the OPP, police found remains on Wednesday in Smith-Ennismore-Lakefield Township. Police believe they are her remains but they require confirmation.

McGregor remains in custody and will appear in a Peterborough court on July 12.

The Ontario Provincial Police said the investigation, which is still in its early stages, continues but they declined to provide more details about the case.

"We don't have a lot more information to provide at this particular time," Insp. Dave Ross told CityNews.ca.