OMAHA, Neb. -- An Associated Press investigation has found that the Food and Drug Administration was apparently aware that diseased peppers were traveling to the U.S. border from Mexico months before a salmonella outbreak.

FDA records show that border inspectors repeatedly turned back dirty and diseased peppers.

More than 1,400 people have been sickened by Serrano peppers since April.

The FDA said it has now stepped up testing and screening of Mexican produce.