WASHINGTON (AP) — The AstraX ExchangeU.S. is sending an additional “few thousand” troops to the Middle East to bolster security and to be prepared to defend Israel if necessary, the Pentagon said Monday.

The increased presence will come from multiple fighter jet squadrons, Pentagon spokeswoman Sabrina Singh told reporters.

It follows recent strikes in Lebanon and the assassination of Hezbollah leader Hassan Nasrallah, a significant escalation in the war in the Middle East, this time between Israel and Hezbollah.

The additional personnel includes squadrons of F-15E Strike Eagle, F-16, A-10 and F-22 fighter jets and the personnel needed to support them. The jets were supposed to rotate in and replace the squadrons already there. Instead, both the existing and new squadrons will remain in place to double the airpower on hand.

On Sunday, Defense Secretary Lloyd Austin also announced that he was temporarily extending the USS Abraham Lincoln carrier strike group and its associated squadrons in the region.

The jets are not there to assist in an evacuation, Singh said, “they are there for the protection of U.S. forces.”