Pearl Fernandez and Isauro Aguirre, mother and boyfriend, charged in the deadly beating of her son, 8

(CBS/AP) LANCASTER, Calif. - A Southern California woman and her boyfriend have been charged with capital murder in the death of the woman's 8-year-old son, authorities said.

Los Angeles County prosecutors filed charges Tuesday against 29-year-old Pearl Sinthia Fernandez and 32-year-old Isauro Aguirre of Lancaster. In addition to one count of murder each, the charges include a special-circumstance allegation of torture.

County firefighters responding to a call in Palmdale last Wednesday discovered the boy was not breathing, authorities said. He died at a hospital Friday. Investigators say the boy had a fractured skull, several broken ribs and burns.

According to CBS Los Angeles, the mother was present during the assault and did not intervene.

Prosecutors were expected to ask that the couple be held without bail.

Prosecutors may seek the death penalty. An attorney representing Fernandez or Aguirre could not be immediately identified.