The partial government shutdown started Feb. 14 after immigration negotiations between the White House and congressional Democrats collapsed. The funding lapse has required most DHS employees to continue working without pay, while others are furloughed.

Democrats have pushed for limits on federal immigration enforcement in exchange for supporting the funding bill. Among their demands were requiring agents to remove masks, wear body cameras and obtain judicial warrants before entering private property, according to The Associated Press. They also sought to prohibit detaining individuals without first confirming they are not U.S. citizens and to end searches based on race, language, accent or occupation.

DHS spokeswoman Lauren Bis blamed the Democrats’ “refusal to fund DHS” for what she described as “the severe fallout” felt at major airports.

“These political stunts force patriotic TSA officers, who protect our skies from serious threats, to work without pay,” Bis’ statement reads in part. “These frontline heroes received only partial paychecks earlier this month and now face their first full missed paycheck, leading to financial hardship, absences, and crippling staffing shortages.”

William P. Hobby Airport (HOU) in Houston experienced some of the longest wait times in the country on Sunday. Just before 11 a.m., Hobby Airport advised travelers to arrive three or four hours ahead of their flight times, warning TSA wait times may be over two hours. By 1:30 p.m., an update suggested arriving four to five hours early and to prepare for TSA wait times to exceed three hours.

“We appreciate your patience and understanding as our federal partners work to maintain the safety of all passengers,” the Houston airport said.

Besides Hobby Airport, Louis Armstrong New Orleans International Airport (MSY) also advised passengers to arrive three hours early.

“Due to impacts from the federal government’s partial shutdown, the TSA is experiencing a shortage of workers at the security checkpoint, which is causing longer-than-average lines,” the Louisiana airport explained in a social media post. “The Airport has staff on hand to help keep the lines organized, and we will continue to coordinate with our federal partners with the TSA as they navigate this issue.”