Southwest Airlines (LUV) said it is manually checking it passengers after its online check-in system shutdown earlier Thursday afternoon.

The Dallas-based carrier said around 4:30 ET Thursday that the system was shut for at least two hours. However, it has yet to experience delays and cancellations.

The shutdown affects check-ins through its website and at kiosks inside the airport. As of now, customers can only check-in at the airport through customer service counters and gates.

Tech personnel at Southwest are working on the issue, a spokesperson said.

The hiccup comes two weeks after the carrier, which closed its $1.4 billion acquisition of AirTran last May, reported a better-than-expected first-quarter loss.

Southwest operates more than 3,000 flights a day.

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