INCIRLIK AIR BASE, Turkey — Defense Secretary Leon E. Panetta signed an official deployment order Friday to send 400 military personnel and two Patriot air defense batteries to Turkey as its cross-border tensions intensify with Syria, where loyalist forces have increasingly resorted to aerial attacks, including use of ballistic missiles, to fight a spreading insurgency.

The US batteries will be part of a broader push to strengthen Turkey’s defenses that will include the deployment of four other Patriot batteries — two from Germany and two from the Netherlands. Each battery contains multiple rounds of guided missiles that can intercept and destroy other missiles and hostile aircraft flying at high speeds.