WASHINGTON — The Pentagon on Monday announced which troops would be among the first of the 30,000-35,000 additional troops to head to Afghanistan.

Secretary of Defense Robert Gates began working on the orders last week on the flight back from the United States Military Academy at West Point, N.Y., where he'd watched President Obama announce the new strategy.

In all, the Pentagon announced Monday the deployment of 16,200 troops.

From the Marines, the deployment groups were: -- Task Force 1st Battalion, 6th Marines, based at Camp Lejeune, N.C., with approximately 1,500 Marines, deploying before the end of December 2009 -- Regimental Combat Team-2, headquartered at Camp Lejeune, N.C., with approximately 6,200 Marines, deploying early spring 2010. -- I Marine Expeditionary Force (Forward) headquarters from Camp Pendleton, Calif., with approximately 800 Marines, deploying spring 2010. These units will bring the total number of Marines deployed to Afghanistan to approximately 19,500.

From the Army:

-- lst Brigade Combat Team, 10th Mountain Division, Fort Drum, N.Y., with approximately 3,500 soldiers, deploying spring 2010. They are tasked with training Afghan security forces

-- In addition, another 4,200 Army Combat support troops, including military police will be deploying spring 2010.