Privateers

Privateers (プライベーティア) are a type of mercenaries employed by the Russian army as deniable soldiers to carry out dirty and illegal works for Russia.

Etymology
As part of naval warfare, from the 16th to the 19th century, s were pirates authorized by a nation's government to attack foreign shipping, entitled by their state to attack and rob enemy vessels during wartime in order to cause economical damage. Some were so successful, like the famous Sir Francis Drake, that they were knighted.

Principles
Privateers are "blank" units, with no official members, rumored to be recruited over the Internet from violent people with military experience centered around Western Europe. As a result of their clandestinity, missions that would bring criticism from the international community can be carried out smoothly, and if they get caught, Russia can pretend to throw them in detention as punishment while they actually get off scot-free. They are paid handsomely and are given Russia's best equipment, like tanks and helicopters.

According to Digurv, they were created as a result of needing people to carry out missions to cut off enemy supply lines, which were not popular with regular soldiers.

World War III
The privateers attack the village Hamazura Shiage and Takitsubo Rikou are hiding in and they help the villagers defend themselves.