Toronto police have charged a 42-year-old man with first-degree murder in the deaths of Nighisti Semret, 55, and Rigat Essag Ghirmay, 28.

Adonay Zekarias, 42, who came to Canada from Eritrea in 2009 and is a permanent resident, was initially arrested on May 27 at his apartment at 101 Humber Blvd. S. and charged with indignity to a dead body in relation to Ghirmay.

Ghirmay’s remains were found in a duffel bag by a creek near Alliance Avenue and Humber Boulevard on May 24.

Police have now upgraded that charge to first-degree murder, and he faces the same charge in the fatal Cabbagetown attack on Semret. Zekarias made a court appearance Monday and remanded into custody.

Semret was stabbed to death in an alley near Bleecker Street on Oct. 23, 2012.

The accused, and both victims, all hail from Eritrea, and police now say they were known to each other.

“Evidence will show Semret and the offender knew each other,” said Det. Sgt. Gary Girioux. “But the motive for the attack on Semret remains unclear.”

Police are working on a theory that Ghirmay may have been murdered because she had knowledge of Semret’s killing.

“It’s my personal theory that Rigat did know or had figured out what Mr. Zekarias had (allegedly) done and (possibly) confronted him,” said Sgt. Det. Pauline Gray.

Police said DNA evidence was crucial in their investigation, and allege Zekarias’ skin was found under Semret’s fingernail.