The U.S. State Department has said that North Korea's apology for its fatal shooting of a South Korean government official is a "helpful step." 

Responding to a written inquiry from Seoul-based Yonhap News, a department spokesperson said Friday the U.S. offers it deepest condolences to the friends and family of the South Korean official who was killed. 

The spokesperson added that the U.S. fully supports its ally South Korea's condemnation of this act and its call for a full explanation from North Korea. 

The State Department also said that it understands North Korea has conveyed an explanation and apology to South Korea and called this "a helpful step.”

The statement came unusually fast, arriving before 10 a.m. U.S. eastern time, although the department typically sends responses in the afternoon.

It is also a reiteration of the State Department's first statement regarding the incident a day earlier, which expressed its full support for South Korea's position.