Police have arrested a 48-year-old Mississauga man after his common-law wife was killed overnight.

After getting a 911 call about domestic trouble shortly after 1 a.m. Saturday, officers arrived at an apartment on Glen Erin Drive, near Derry Road West, to find a woman who lived there with critical injuries.

Marilyn Dellaire, 56, was pronounced dead at the scene, and her longtime common-law husband, Doug McCoy, was arrested and charged with second-degree murder.

He was to appear in a Brampton court on Saturday.

Homicide detectives are asking anyone who can help with their investigation to call (905) 453-2121, ext. 3205, or Peel Crime Stoppers anonymously at 1-800-222-TIPS (8477).