Police are renewing the push for tips in the 10-year-old murder of Lisa Leckie, who was found dead in her south London apartment.

Leckie's common-law husband returned from work around 7 a.m. on March 24, 2009 and found her body.

The 25-year-old was found, asphyxiated, in her third-floor apartment at 390 Southdale Road East. Her eight-month-old son was found unharmed in his crib.

Police believe she was killed earlier that morning or the evening before.

Investigators have now released information on a typewritten note left by her killer at the scene.

While no information on the contents of the note were released, police believe the simple fact a typewriter was used may jog someone's memory.

London police Det.-Sgt. Alez Krygsman said in a press release, “Even in 2009, it was unusual to find something written on a typewriter instead of produced by a computer printer."

Investigators also believe Leckie was targeted by someone she new, based on the note and other evidence, and that someone knows who it was.

Her now 18-year-old son Sean Leckie is adding his voice to the call for public help. Police released a video statement from him on Friday where he says he can't believe that it's been 10 years since her death.

Speaking with CTV News, he says "I can't even remember my mother's voice and that breaks my heart."

He wasn't at home that night with his mother and brother, but remembers hearing the news and thinking it couldn't be real.

Now he hopes someone will hear his plea and come forward, "I don't know who is out there, but we have to believe someone is out there with information."

Anyone with information is asked to contact police at 519-661-5674 or Crime Stoppers.