AUSTIN, Texas (AP) – Protests over Texas Gov. Greg Abbott’s latest border security measure are slowing down the flow of trade on the U.S.-Mexico border.

Since Monday, Mexican truckers have blocked the Pharr-Reynosa International Bridge in protest after Abbott last week directed state troopers to pull over and inspect trucks coming into Texas.

Unusually long backups have also been reported elsewhere along Texas’ 1,200-mile border with Mexico.

Abbott says the extra inspections are needed to curb human trafficking and the flow of drugs.

But critics question how the inspections are meeting that objective, and experts say grocery shoppers could notice shortages as soon as later this week.

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