Police allege Roberts broke into a residence and stole a knife that they allege he used to kill Joao Nascimento, 93, and Maria Nascimento, 81.
Police spokesman Scott Pattison says a neighbour reported a suspicious person seen loitering in the area on Friday.
Pattison say police discovered the bodies of the two victims when they entered their residence.
Police say the cause of death will be officially confirmed following autopsies scheduled for Tuesday.
Pattison says the couple had been married for forty years and their sudden death was “extremely tragic.”
“(They were) in the latter years of their life, living a peaceful existence,” he says.
Pattison could not speculate on a motive but says investigators believe the couple were “random targets.” It’s not known when Roberts will appear in court.