Flight 957 landed safely at Cleveland Hopkins International Airport, FAA spokeswoman Elizabeth Cory said.Southwest said the unscheduled stop came from a reported crack to the outer pane of the multi-pane window. Passenger Linda Holley texted her son Ryan with a picture of the damaged window. "Window on plane cracked during flight. Landing in Cleveland to be safe. Everything ok but scary," one of her texts read. In another, she said: "Yes Southwest. Just heard loud noise. Very large crack with piece of window missing at bottom. Just landed. Everything ok. Don't know plan yet"The FAA said it will investigate what caused the window to crack. So far, the cause is not known. There was no depressurization in the cabin, and therefore the oxygen masks were not deployed, FAA spokesman Greg Martin said. He said the pilot did not declare an emergency but did ask to divert to a nearby airport.It was the second high-profile flight diversion by a Southwest plane in less than three weeks.On April 17, Southwest Flight 1380 made an emergency landing in Philadelphia after an engine failed midflight.Jennifer Riordan, a philanthropist and Wells Fargo executive, died after being partially sucked out of a window. But passengers and even President Donald Trump lauded the captain, Tammie Jo Shults, for safely landing the plane.
CNN's Rene Marsh, Tony Marco and Holly Yan contributed to this report.