Arrests of illegal immigrants by the Border Patrol declined in 2008 to 724,000, the lowest number in 35 years, the Department of Homeland Security reported. Apprehensions by the agency fell from a peak of 1.6 million in 2000, declining by 39 percent in the last three years. Border Patrol arrests are regarded by researchers as a broad-brush indicator of the flow of illegal immigrants. The department’s report attributed the decline to high unemployment in the United States and increased border enforcement, among other factors.

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