Toronto police say a mother and her boyfriend have been charged with second-degree murder in the death of the woman's two-year-old son.

The toddler, identified as Nicholas Cruz, died in hospital Sunday after he was assaulted, said homicide squad Det. Sgt. Hank Idsinga.

An autopsy revealed signs of abdominal trauma that was a contributing factor in the boy's death, Idsinga told CP24 reporter Sue Sgambati.

Detectives were alerted after the toddler arrived at Toronto Western Hospital without vital signs and was later pronounced dead.

The boy was taken to the hospital by his mother and her boyfriend, and staff discovered "suspicious" injuries, Idsinga said.

Marleny Cruz, 25, and Joel France, 36, are charged with second-degree murder. France is also charged with assault.

Both appeared briefly in court Tuesday and were remanded into custody.

Police remained at the couple's Walnut Avenue home Tuesday.

The boy is Toronto’s 31st homicide victim of 2013.

Anyone with information about the homicide is asked to call police at 416-808-7392 or Crime Stoppers anonymously at 416-222-TIPS (8477).

With files from CP24 reporter Sue Sgambati and CTV Toronto reporter Tamara Cherry.

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