Second-degree murder and aggravated assault charges are pending following the deaths of two women in a stabbing attack in Calgary.

The victims are thought to be the estranged wife of the suspect and her close friend, say police.

A woman ran out of a home in southeast Calgary screaming and covered in blood Sunday evening. Neighbours tried to give her medical assistance, but she was taken to hospital where she was declared dead.

Another woman, who police say they believe is the estranged wife of the suspect, was found dead in the doorway of the home. Her identity has not yet been released.

Autopsy results were released Monday afternoon for Fahmida Velji-Visram, 29, the woman who had run out of the house.

It's been determined that she died from stab wounds. Autopsy results for the other dead woman are pending.

Two women were killed and a third was wounded in a stabbing attack in southeast Calgary on Sunday evening. A suspect has been arrested. (Kyle Bakx/CBC)

A third woman was taken to hospital in non-life-threatening condition, but has since been released. She is reported to be the daughter of the landlord who lives in the upstairs of the house. She had gone down to investigate the commotion.

Officers arrested a male suspect near the scene and took him to hospital, suspecting he had ingested an unknown substance.

'So shocking to see'

Ebenezer Choebefu, a neighbour who knew the people living in the house, told CBC News he and his wife witnessed the horrible scene as it unfolded.

He said a young girl from the house ran over to them.

There had been an argument, but Choebefu said they didn't ask the girl what it was about because it was so traumatic.

"I haven't been able to sleep. I knew them very well," said Choebefu.

"Such friendly people. So shocking to see,” he said.

Neighbour Leon Kemp was driving by with his daughter when he saw the commotion.

"I said to my daughter, this just does not look normal, we're stopping here," said Kemp.

"I thought she had been hit by a car, but it didn't explain all the blood."

Police said they don't believe the attacks were random.

The stabbings appear to have happened in a basement suite, according to Choebefu.

Police said they were called to the home on April 9 because of an argument, but no charges were laid.

The city is still reeling from last month's stabbing attack in the Brentwood area that killed five people.