Airlines are cutting their first-quarter profit and sales estimates, warning that a weaker economic backdrop is weighing on travel demand.

Ahead of a JPMorgan industry conference, American Airlines on Tuesday said it expects to lose between 60 cents a share to 80 cents a share in the first three months of the year, a wider loss than the 20 cents to 40 cents a share it previously forecast. It said revenue would likely be flat on the year compared with a January estimate of a rise of as much as 5%.

American said in a securities filing that “the revenue environment has been weaker than initially expected due to the impact of Flight 5342 and softness in the domestic leisure segment, primarily in March,” referring to the deadly collision of one of its regional jets and an Army helicopter in Washington D.C. in January.

The forecast followed Delta Air Lines slashing its first-quarter estimates after the market closed Monday. Delta said its outlook was “impacted by the recent reduction in consumer and corporate confidence caused by increased macro uncertainty, driving softness in Domestic demand.”

Airline shares extended their losses on Tuesday morning in premarket trading, with Delta down more than 8% and American down nearly 4%.

Southwest Airlines also cut its revenue guidance, to up no more than 4%, down from a forecast of as much as 7% for the first quarter over last year.

In addition to leisure travel, carriers have said also noted a sharp decline in government travel since the start of the latest Trump administration.

This is a developing story. Please check back for updates.