The Transportation Security Administration says despite a huge drop in air travel since the start of the COVID-19 pandemic, the agency's officers found three times as many firearms last month in carry-on luggage as they did during the same period last year.

In a statement, the agency said the statistic was "particularly alarming, given that TSA screened about 75% fewer passengers in July 2020, over the previous year's volume." It said in 2019, its officers detected 5.1 guns per million travelers as compared with 15.3 guns per million travelers last month.

"Even more concerning is that 80% of the firearms coming into the checkpoint are loaded and it's just an accident waiting to happen," TSA Administrator David Pekoske said.

"Travelers need to know that if they bring a gun to the security checkpoint, regardless of whether it is in a handbag, knapsack, roller-bag or strapped to their belt, it will be an inconvenient and expensive mistake on their part," he said.

The federal penalty for an unloaded firearm starts at $2,050 – double that for a loaded gun, the statement said. The maximum penalty can go up to $13,669 per violation, depending on the circumstances, it said.

While the reason for the sudden upsurge is not clear, gun sales have skyrocketed since the beginning of the year, "especially following COVID-related outbreaks and shutdowns and many large protests against the police," Daniel W. Webster, a professor at Johns Hopkins University's Bloomberg School of Public Health, told NPR in an email.

Based on estimates derived from pre-purchase background checks, July marked the second-highest month on record for U.S. gun sales, he noted.

"So the same fear of victimization related to COVID and protests against the police could be spurring more people to routinely carry guns outside the home, including when they go to get on a plane," Webster told NPR.

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