More than three million people passed through United States airport security on Sunday, marking a new record as travel surges, according to the US Transportation Security Administration (TSA).

This milestone surpassed the previous record set on June 23, with eight of the 10 busiest days in TSA's history occurring this year, exceeding pre-COVID-19 pandemic levels.

TSA was established after the September 11, 2001 attacks and oversees security checks for passengers, handling 35 individuals per second on Sunday.

Travel costs, including airline tickets and hotel prices, have decreased significantly from a year ago, making travel more accessible and contributing to increased travel demand in the United States.

Airlines, though experiencing losses in the first quarter, anticipate a profitable summer with full planes and positive second-quarter results expected by major carriers.

However, increased air travel has also led to a rise in passenger complaints, with the US Department of Transportation receiving a record number of grievances in 2023.

This surge in complaints highlights ongoing challenges faced by airlines amidst the resurgence in air travel post-pandemic.