A number of U.S. military bases in Europe were placed on high alert over the weekend of June 29 and 30, and the force protection level was raised to the second-highest level amid fears that U.S. troops or facilities could be subjected to a terrorist attack. This was reported by CNN, citing two unnamed U.S. officials.

These military bases, including the U.S. Army garrison in Stuttgart, where the headquarters of the U.S. European Command in Europe (USEUCOM) is located, on June 30 strengthened the defense of the armed forces to the "Charlie" level, the interlocutors pointed out. According to the U.S. Army, that level is used "when an incident occurs or there is intelligence indicating the likelihood of a terrorist attack or attack on (military) personnel or installations," DW reported.

A CNN source at a U.S. military base in Europe emphasized that this level of threat has not been seen there in "at least 10 years." He said it usually means the military is aware of an "active threat."