CAMP PENDLETON — Thousands of San Diego-based troops are now headed to the Middle East as the U.S. military expands its presence in the region amid the ongoing conflict with Iran.

The 11th Marine Expeditionary Unit, made up of at least 2,200 Marines based at Camp Pendleton, deployed ahead of schedule aboard the USS Boxer amphibious assault ship, NBC News reported Friday, citing two people familiar with the decision. A Navy spokesperson described the deployment to NBC 7 as a routine operation in the Indo-Pacific, saying the Boxer Amphibious Ready Group is conducting training to ensure the continued war-fighting readiness of Navy and Marine forces.

Marine Expeditionary Units are trained for crisis response, including evacuations from dangerous areas, embassy protection and establishing footholds for follow-on forces such as special operators. The early deployment suggests a heightened operational tempo as the U.S.-Israel conflict with Iran enters its fourth week with no end in sight.

The USS Boxer deployment follows the redirection earlier this week of two other amphibious assault ships — the USS Tripoli and USS New Orleans — from the Philippine Sea to the Middle East. Altogether, the additional deployments will add roughly 5,000 Marines and sailors to the region, on top of forces already engaged in air strikes that have, according to U.S. and Israeli officials, severely degraded Iran's military and leadership.

For East County and San Diego families with loved ones at Camp Pendleton, the accelerated deployment is a stark reminder of how directly the conflict is touching home. The Pentagon has requested an additional $200 billion from Congress to fund the war. More than 2,000 people have been killed across the Middle East since the conflict began, including 13 U.S. military members.