Murder charges have been laid against a man and a woman in connection with the July slayings of four people found dead in Calgary over a two-day period, and police now say all six people involved were known to each other.

Tewodros Mutugeta Kebede, 25, and Yu Chieh Liao, 25 — who were identified as persons of interest three weeks after the killings — are charged with first-degree murder in the death of Hanock Afowerk, 26, and three counts of accessory after the fact in the slayings of Cody Pfeiffer, 25, and sisters Tiffany Ear, 39, and Glynnis Fox, 36.

The bodies of Pfeiffer, Ear and Fox were discovered in a burned-out car in Calgary on May 10, 2017. Two days later, Afowerk's remains were found near a road west of the city.

Homicide charges still have not been laid in connection with the three victims found in the vehicle, and although Kebede and Liao are also considered suspects in those deaths, Insp. Paul Wozney said the investigation is "full steam ahead" and police believe there are others involved.

Investigators link victims to accused

Police are now backtracking on prior statements that the victims found in the vehicle were in the "wrong place at the wrong time."

"All six of these people were known to one another," said Wozney. "Investigative theories sometimes change."

Investigators believe the suspects may have burned clothing near the Canadian Forces base in Moose Jaw, Sask., or at a nearby airport and are asking locals, particularly farmers in that area of Saskatchewan, to keep an eye out for suspicious-looking burned items.

"If you're scared, if you feel intimidated, we would be able to provide you with assistance if you come forward with information," said Wozney.

A vehicle belonging to the Calgary Police Service's forensic crime scenes unit was parked outside the site where three bodies were found in a burned-out car in the northwest Calgary community of Sage Hill in July. (Monty Kruger/CBC)

Liao and Kebede made brief appearances in a Calgary courtroom on Wednesday. Liao was in person, while Kebede made a video appearance from the Calgary Remand Centre. The case was put over for three weeks while Kebede looks for a lawyer.

Kebede is also accused of wearing a disguise and possessing a gun during an armed robbery against a husband and wife on June 29, 2017, which is believed to be unrelated to the homicides.

From left to right: The bodies of Glynnis Fox, Hanock Afowerk, Cody Pfeiffer and Tiffany Ear were found in July at two different locations. (Facebook/Megan Snell/Calgary Police Service)

On July 10, the first three victims — Pfeiffer, Fox and Ear — were found dead in a burned-out car in the northwest Calgary neighbourhood of Sage Hill.

Afowerk, who owned the vehicle, was found deceased two days later west of Calgary near the traffic circle where Highway 22 and Highway 8 meet.

Police said they believed all four deaths were connected and that the three people in the car were caught up in a targeted attack against Afowerk.

Pfeiffer was described by a friend as "a small town kid with a big heart."

The sisters were described by family members as "beautiful souls" who left behind 16 children between them.

A cousin said Fox and Ear, who were born and raised in Morley — an Indigenous community west of Calgary — had a difficult youth and still struggled at times in adulthood.

Police in other cities thanked

Two weeks after the bodies were discovered, Kebede was taken into custody in Toronto on drug charges unrelated to the homicides.

Days after that, police arrested Liao, who had been identified as a person of interest in connection with the killings, in Toronto. She was wanted on a Canada-wide warrant for fraud.

At the time, police said Liao was believed to have played a "significant role" in what officers described as the brutal and ruthless slaying of four people.

Kebede has a criminal history in Toronto, including convictions for assault and drug trafficking.

Other policing agencies — including Moose Jaw, Medicine Hat, RCMP and the Toronto guns and gangs unit — have "bent over backwards" to help Calgary police with what Wozney described as a "complex" investigation.