CHARLOTTE, N.C. – Prosecutors announced Thursday that they’ll seek the death penalty against a couple accused of kidnapping an 11-year-old and killing her grandparents in April.

Nikkia Cooper, 25, and Curtis Atkinson Jr., 36, are both charged with the murders of Atkinson’s parents, Curtis and Ruby Atkinson.

Nikkia Cooper mugshot
<p>Nikkia Cooper</p>

Investigators said the couple also kidnapped 11-year-old Arieyana Forney, Atkinson's niece, and took her to Washington D.C., where police located their vehicle.

An autopsy revealed that Atkinson's 63-year-old father was stabbed a total of 60 times during a brutal attack. Of those stab wounds, 36 were to the face and neck with another 22 to the chest. Officials also determined that Atkinson suffered from blunt force trauma to the head and neck.

This is a developing story. Please stick with WCNC.com as more details become available.