A Southwest Airlines flight traveling from Las Vegas to Philadelphia on Saturday was diverted to Indianapolis after a pressurization warning light illuminated in the plane's cockpit. The aircraft, however, did not depressurize.

Flight 5913 landed safely at the Indianapolis International Airport as a precaution and passengers boarded another plane. The flight continued to Philadelphia and arrived about 9:30 p.m., about 4½ hours behind schedule, a Southwest spokeswoman said.

Last month, an engine on Southwest 1380 from New York City to Dallas exploded over Pennsylvania and the flight made an emergency landing in Philadelphia.

Jennifer Riordan, a bank executive from New Mexico, was fatally injured after she was partially sucked out of the plane. The National Transportation Safety Board said one of the engine's blades snapped, hurling debris that broke a window.

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Earlier this month,  some passengers on a Southwest Airlines flight from Denver sustained minor injuries when the plane appeared to suddenly lose cabin pressure as it neared Dallas. Flight 861 had 120 people on board on May 14 when oxygen masks deployed and the pilots declared an emergency as the plane approached Dallas Love Field.

Southwest said in a statement that the flight crew reduced altitude but that the cabin did not depressurize.