Shelby Herchak is taken into custody Tuesday night at the Calgary police arrest processing unit downtown. (Stuart Dryden, QMI Agency)

CALGARY - The Calgary mother of an infant killed after sustaining serious head injuries has been charged by police with a second-degree murder.

Daniel Herchak, 26-days-old, was rushed to the Alberta Children's Hospital where he died Aug. 9.

An autopsy determined that the cause of infant’s death was blunt force trauma to the head.

Investigators believe the injuries were not accidental.

Shelby Anna Herchak, 18, the baby's mother, has been charged in the murder.