The manslaughter trial of a Winnipeg mother got underway in a courtroom on Monday.

Michelle Camire is on trial for the death of her three-month-old son Michael Helgason in October 2004.

The jury was told that Camire became frustrated and threw the baby into his bassinette in a townhouse in North Kildonan.

An audiotape of her 9-1-1 call was played.

She told the operator she got frustrated and slammed him down.

A pathologist testified the boy died from a brain injury.

The trial is expected to last only a few days and wrap up this week.