WASHINGTON – The U.S. Marine Corps

said Tuesday it has been authorized to recall thousands of Marines to active duty, primarily because of a shortage of volunteers for duty in Iraq and Afghanistan.

Up to 2,500 Marines will be brought back at any one time, but there is no cap on the total number of Marines who may be forced back into service in the coming years. The call-ups will begin in the next several months.

This is the first time the Marines have had to use the involuntary recall since the early days of the Iraq combat. The Army has ordered back about 14,000 soldiers since the start of the war.

Marine Col. Guy A. Stratton, head of the manpower mobilization section, estimated that there is a current shortfall of about 1,200 Marines needed in upcoming unit deployments.

The call-up affects Marines in the Individual Ready Reserve, a segment of the reserves that consists mainly of those who left active duty but still have time remaining on their eight-year military obligation.

Generally, Marines enlist for four years, then serve the other four years either in the regular Reserves, where they are paid and train periodically, or they may elect to go into the IRR. Marines in the IRR are only obligated to report one day a year but can be involuntarily recalled to active duty.

According to Stratton, there are about 59,000 Marines in the IRR, but the Corps has decided to exempt from the call-up those who are either in their first year or last year of the reserve status. As a result, the pool of available Marines is about 35,000.

The deployments can last up to two years, but on average would be 12 to 18 months, Stratton said. Each Marine who is being recalled will get five months to prepare before having to report for duty.