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     MADRID, Spain (CNN) -- Passengers said they saw flames and then heard an explosion moments before a Spanair jet crashed on takeoff Wednesday at Madrid's Barajas Airport, killing 153 people, according to local media.
     The Spanair Flight JK5022 was carrying 172 people. There were 19 survivors, including two infants, Development Minister Magdalena Alvarez said. The 19 were being treated at a hospital, Alvaraez said. The severity of the injuries varies, but many of the injured have been treated for burns, Spanish Red Cross spokeswoman Olivia Acosa said.
     The flight was bound for Las Palmas in the Canary Islands, two hours away. Local officials said one of the engines caught fire. The aircraft, an MD-82, has two jet engines, both at the rear.
     The crash sent up a plume of smoke visible from several kilometers away. At the time of the crash, weather conditions were hot and clear. A survivor told Spain's ABC newspaper that she and other passengers heard an explosion as the plane was taking off.
What was the cause of the plane explosion?