It looks like the military build-up in eastern Europe continues.

The US Air Force is deploying 12 F-15C belonging to the 125th Fighter Wing, Florida Air National Guard, Jacksonville, Fla., to Europe.

The Eagles, part of the first Theater Security Package (TSP) will first operate from Leeuwarden airbase, in the Netherlands.

They will take part in the Frisian Flag multinational exercise and are then expected to move east and be temporarily based at Graf Ignatievo, Bulgaria.

The Air National Guard F-15s are the second TSP to deploy to Europe in support of Operation Atlantic Resolve, the mission aimed at showing Washington’s commitment to peace and stability in the region and reassure local allies amid growing tensions with Russia following the annexation of Crimea last year.

Last month, 12 A-10s of the 355th Fighter Wing at Davis-Monthan Air Force Base, Arizona, deployed to Germany as part of the first theater security rotation on the continent. The unit first flew from Spangdahlem air base, and then moved to RAF Lakenheath, UK, and to Poland.

TSPs are not the only US forces currently operating from Europe: 14 F-16s from Aviano airbase have deployed to Estonia to conduct joint training with local military forces.