The mother of a CIA operative killed in the 2012 attack on a U.S. diplomatic facility in Libya says the spy agency has agreed to pay a death benefit even though his parents were not entitled under a standard federal insurance policy he held that pays a survivor benefit only to spouses and dependents.

The mother, Barbara Doherty, on Wednesday called the expanded benefit "symbolic justice." Her son, Glen Doherty, was killed, along with three other Americans, in an attack on a CIA facility in Benghazi. He was divorced and had no children.

The CIA said in a statement that the expanded benefit is retroactive to 1983 and applies to survivors of all federal employees, including contractors, killed overseas in the line of duty and as a result of terrorism.