U.S. Customs and Border Protection was conducting an exercise at the San Ysidro Port of Entry Wednesday morning that may have briefly interrupted border crossings, the agency said.
People crossing the border south of San Diego could see CBP agents conducting what the agency calls an operational readiness exercise starting at 10 a.m.
During the exercise, which lasted about 30 minutes, several loud bangs could be heard as CBP agents gathered around the main crossing gates. An announcement on a loudspeaker in both English and Spanish alerted drivers that a training exercise was taking place.
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"CBP continually assesses the capabilities of our facilities and has been making — and will continue to make — necessary preparations. Preparations include participating in operational readiness exercises and the mobilization of resources, as needed, to ensure the facilitation of lawful trade and travel," CBP said in a statement.
The San Ysidro Port of Entry is the busiest land border crossing in the United States. The crossing has been closed to "non-essential" travel due to the coronavirus pandemic since March 2020.