According to Sergeant Walter Morris, It was a secret mission called Operation Firefly.

Entity and relation annotations:
id: 0
type: entity
value: text: Walter Morris
labels: <Person>
id: 1
type: entity
value: text: Sergeant
labels: <Title>
id: 2
type: entity
value: text: Operation Firefly
labels: <Event>
type: relation
to_id: 1
labels: Person:holds_title:Title
from_id: 0