Washington (CNN) -- A year and a half after deploying National Guard troops to counter illegal immigration on the Southwest border, the Department of Homeland Security and Pentagon told Congress Tuesday they are cutting the number of troops and changing their mission. The drawdown, which the department characterized as a "transition," will begin in January and should be completed by March. Several lawmakers told CNN the number of National Guard troops on the border will be cut from 1,200 with responsibilities mainly on the ground to 300 who will support the border mission in the air. The Department of Homeland Security said the change is possible because of a jump in the number of Border Patrol officers in the region, an increase in technology and a drop in apprehensions at the border.
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The transition will begin in January and be completed by March, DHS says
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Some lawmakers oppose the move, saying conditions merit more troops, not fewer
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DHS says a "new strategic approach" will increase border security
The @placeholder said that in the fiscal year ending October 1, Border Patrol apprehensions of illegal immigrants -- a key indicator of the amount of illegal immigration -- decreased to 340,252, down 53 percent since fiscal year 2008.
Since 2004, the size of the @placeholder has doubled to 21,444.