A U.S. Border Patrol agent checks a car on the I-93 southbound lane on Wednesday, September 28, 2017 south of the Route 175 exit south of Lincoln. Geoff Forester

A three-day immigration checkpoint held on Interstate 93 earlier this month failed to net any arrests, the U.S. Customs and Border Protection agency said Thursday.

Held between Aug. 20 and 23, the stop was the latest in a recent string of checkpoints carried out by the federal agency over the past year. Drivers passing through Lincoln in the southbound lanes of I-93 were stopped briefly and asked to confirm their citizenship, with drug-sniffing dogs nearby.

While a similar stop in May resulted in 22 people arrested on immigration charges, and a June stop produced five arrests, federal agents came up empty this month, according to CBP spokeswoman Stephanie Malin. That may partly be the result of weather complications, she said.

“I can confirm checkpoint operations were run on Interstate 93 in New Hampshire from Aug. 20 to 23, however, the checkpoint was not operational a significant portion of the time due to inclement weather,” she said. “No arrests were made at the checkpoint.”

Years ago, the checkpoints were a once-yearly occurrence. Then in 2012, the border checkpoints were discontinued under the Obama administration. But a rush of new funding and a shift in priorities under President Donald Trump saw the practice return twice last year, in August and September. Since then, six stops have been planned for this year, state police emails revealed; three have been carried out so far.

Inland border checkpoints as they are called – those positioned up to 100 miles of the physical border – have been in use since at least 1953, when a U.S. Department of Justice rule was passed authorizing the practice. Agents are allowed to ask anyone driving through about their immigration status, courts have ruled.

The stops have proven controversial, with groups like the American Civil Liberties Union of New Hampshire opposing them as unwarranted intrusions. Meanwhile, the agency and its supporters say the stops are a key means to cut off undocumented travelers heading from Canada to Boston, and intercept drugs in the process.

Earlier this year, a state district court judge ruled in favor of the ACLU, which had argued the evidence to support drug charges was illegally obtained because the use of drug-sniffing dogs violated the constitutional protection against unreasonable searches and seizure.

Throughout their use, the number of arrests at the checkpoints have varied widely. In the first revival in August 2017, 25 people were arrested; the following month’s stop brought in only eight.

Gilles Bisonnette, legal director for ACLU New Hampshire, argued that the lack of arrests demonstrated that the checkpoints are invasive and ineffective.

“To me, it highlights the significant intrusion that these checkpoints have had on individuals in New Hampshire juxtaposed with the little utility that they have,” he said. “Here no immediate arrests were made while hundreds if not thousands of individuals were detained without any reasonable evidence that they had committed a crime.”