Not a fan of lengthy lines at airport security checkpoints? You aren’t alone: American Airlines is putting the Transportation Security Administration on blast for the kind of “unacceptable” long wait times that caused 6,800 customers to miss their flights during spring break week this year.

“The lines at TSA checkpoints nationwide have become unacceptable,” American spokesman Ross Feinstein said in a statement reported by NBC. “The result: our customers are waiting in TSA lines greater than one hour.”

That issue was “exponentially” worse in the first three months of 2016, which is usually a slow season for air travel.

American says almost 6,800 passengers missed their flights between March 14-20, when many travel to spring break destinations, because of checkpoint delays. The worst airports included Los Angeles, Miami, Atlanta, Dallas, and Philadelphia.

And it’s only going to get worse, Feinstein warns, as the travel season heats up.

“As we approach spring and summer, we are concerned that these lines will grow even longer,” Feinstein said.

American isn’t the only loud voice railing at the TSA right now, NBC notes: on Wednesday, the head of Charlotte-Douglass International Airport wrote to the TSA complaining about insufficient staffing at its checkpoints. Both the Seattle-Tacoma International Airport and Atlanta’s Hartsfield-Jackson International Airport have threatened to replace TSA workers with private security contractors.

American Airlines Hits Out at ‘Unacceptable’ TSA Lines [NBC News]

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