SANTIAGO DE COMPOSTELA, Spain (AP) — Spanish police say they will question the driver in a deadly train derailment for possible "recklessness."

The driver, who's hospitalized with injuries from the crash, is being guarded by police and hasn't yet been interviewed. Police say the questioning might be delayed because of his injuries.

He was officially arrested late yesterday in the hospital where he's recovering.

Investigators have opened a probe into possible failings by the 52-year-old driver and by the train's internal speed-regulation systems.

The train was going far above the speed limit into a curve when it toppled over on Wednesday, killing 78 people.

But the railway company is defending the driver, saying he had an "exhaustive" understanding of the rail line. He's described as a 30-year employee of the state rail company who became an assistant driver in 2000 and a fully qualified driver in 2003. The company says he had driven trains past the site of the accident 60 times.

At the crash scene, crews have been using a crane to lift smashed and burned-up rail cars, loading them onto flat-bed rigs to cart them away. The shattered front engine sat just off the tracks, as passenger train services chugged close by.

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115-c-09-(Alan Clendenning, AP correspondent)-"not happen today"-AP correspondent Alan Clendenning reports investigators want to talk to the train driver but it's unclear when that will take place. (26 Jul 2013)

<<CUT *115 (07/26/13)££ 00:09 "not happen today"

114-c-14-(Alan Clendenning, AP correspondent)-"the black boxes"-AP correspondent Alan Clendenning reports the train's black boxes have been retrieved, but it's unclear how long it'll take to look at them closely. (26 Jul 2013)

<<CUT *114 (07/26/13)££ 00:14 "the black boxes"

APPHOTO PW116: Wrecked carriages sit at a train depot in Padron, near Santiago de Compostela, Spain, Friday July 26, 2013 after they were taken there from the scene of a train accident. Investigators have taken possession of the "black boxes" of the Spanish train that hurtled at high-speed along a curve and derailed, killing 80 people, a court official said Friday. Analysis will be performed to determine why the train was traveling far above the speed limit when it crashed near a station in Santiago de Compostela, in the northwestern Galicia region, said court spokeswoman Maria Pardo Rios. The train's operator remained hospitalised Friday and will be questioned by police but she said the interview will not happen Friday. (AP Photo/Lalo R. Villar) (26 Jul 2013)

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APPHOTO EM106: In this photo taken on Wednesday July 24 2013, A woman is evacuated from a train car at the site of a train accident in Santiago de Compostela, Spain. Spanish police on Friday detained the driver of a train that crashed in northwestern Spain, lowered the death toll from 80 to 78 and took possession of the "black box" of the train expected to shed light on why it was going faster than the speed limit on the curve where it derailed. And in an interview with The Associated Press, an American passenger injured on the train said he saw on a TV monitor screen inside his car that the train was traveling 194 kph (121 mph) seconds before the crash — far above the 80 kph (50 mph) speed limit on the curve where it derailed. (AP Photo/La Voz de Galicia/Monica Ferreiros) (26 Jul 2013)

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