A U.S. Navy air station in Italy faced an imminent security problem and ordered a lockdown and a shelter-in-place warning on Wednesday.

Naval Air Station Sigonella, located in Sicily, Italy, was ordered to take precautionary measures because of an “ongoing situation” at the base’s entry, according to reports. The station is an integral part of naval operations overseas, housing approximately 7,000 troops and their families. Furthermore, given its location in the Mediterranean Sea, the base is considered of great strategic importance for U.S. and NATO forces.