(FOX News) -- Federal lawmakers seeking to pinpoint the number of illegal immigrants who successfully sneak across the southern border ordered up a report from the Department of Homeland Security, but the agency refuses to release it and instead cites a misleading statistic that overstates the number who are nabbed, sources told Fox News.
DHS denied it is holding back the report, but sources say it was completed in November and that it shows roughly half of adults who attempt to cross the border make it.
But that number is at odds with DHS' official estimates. The agency claims authorities catch 80 percent of adults trying to sneak in, but critics say the figure is padded to make it appear border security is more effective than it really is.
If released by the Obama administration, the true numbers could have major implications in the current presidential race, in which illegal immigration and border security have become a key issue, say observers.
One source familiar with the report told Fox News that DHS is suppressing the report for "political reasons . . . because it would 'look bad' and 'help elect Donald Trump."
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