U.S. Army Europe has implemented a ban on travel to Turkey by Defense Department personnel given growing security concerns in the country.
All military and civilian workers, including those with dual citizenship, are prohibited from unofficial travel through Nov. 9, USAREUR announced on its Facebook page.
Official travel requires general officer approval.
After Nov. 9, unofficial and official travel -- including ship-to-shore travel from cruises in Turkey -- will also require general officer approval, USAREUR said.
In addition, DoD employees traveling in Turkey "should avoid public protests, demonstrations, rallies or other large gatherings to the greatest extent possible," USAREUR said. "They should remain alert to suspicious behavior and be aware of their surroundings at all times."
The decision expands travel restrictions already in place.
Since August, the military has restricted all travel to southeastern Turkey, where general officer approval has been required for official and unofficial visits.
"Before making travel plans to Turkey, whether for official reasons or vacation, DoD personnel should talk to their organization's security or antiterrorism officers," USAREUR said.
In September, the Defense and State Departments offered dependents of personnel stationed at Incirlik Air Base and nearby Adana the option of returning to the States and the Air Force suspended families of service members moving to Incirlik.
Those moves followed Turkey's decision to allow the U.S. to fly fighter jets and drones out of Incirlik as part of the U.S.-led air campaign against Islamic State militants in Iraq and Syria.
Turkey, which has also stepped up its involvement in the fight against the Islamic State, has been wracked by violence in recent months. Last month, twin suicide bombings at a peace rally by pro-Kurdish activists in the capital Ankara killed more than 100 people. Authorities said the Islamic State was likely behind those attacks as well as one in July that killed more than 30 people in the town of Suruc near the Syrian border.
Meanwhile, fighting has flared anew between Turkish security forces and Kurdish rebels.