A 25-year-old woman has been charged with murder in connection with the deaths of her two young children in Scarborough.

In a news release on Friday, Toronto police announced that they had laid two counts of first-degree murder against Vanessa Collias.

According to police, Collias fell from a balcony of an apartment building on Glamorgan Avenue, in the area of Kennedy and Ellesmere roads, on the evening of Dec. 10.

She was subsequently located by responding officers on the ground, suffering from critical injuries.

Police then attended a unit to check on the well-being of Collias' children, a four-year-old boy and a five-year-old boy.

When they arrived inside, officers discovered the boys without vital signs. The children were rushed to different trauma centres, where they were pronounced dead.

Their mother was also transported to the hospital, where she remains in serious condition, police said.

Investigators previously said that there were no obvious signs of trauma on the boys when they were found. Their deaths were treated as suspicious pending an autopsy, which was conducted earlier this week.

On Friday, police confirmed that the boys' deaths had been ruled homicides, and as a result, charges were brought against their mother, who appeared in court via telephone and was remanded into custody.

Police said they were not ready to disclose how the children died.

Their identities have not been released, but neighbours told CTV News Toronto on Monday that the boys were named Yiannis and Mimi. They said the boys’ father, Costa Collias, died on Dec. 1 following a battle with leukemia.

"They were cute little four and five-year-olds. They always said hi to me all the time and that's the picture I saw all night long last night was their little faces going 'hi,'" neighbour Steve Rafferty said of the children while speaking with CTV News Toronto on Monday.

A custodian in the building described them as a "happy family."