A 19-year-old woman will be arraigned on charges of involuntary manslaughter and injury to a child in connection with the death of her 7-month-old child, according to Raymondville Police Chief Uvaldo Zamora.

Zamora said the mother, Lydia Estrella De La Rosa, has been detained as investigators seek a motive, and an autopsy has been ordered. 

RELATED STORY: Raymondville mother being questioned following death of 8-month-old child, police chief says

As previously reported, police were investigating "suspicious activity" in connection with the death. The child was brought to Valley Baptist Medical Center where they died.

Police previously said the baby was 8 months old, but Zamora described the child as 7 months old during a Friday press conference. 

This is a developing story, check back for updates.