TOKYO - At least 68 people were killed after a train slammed into a stationary train on the Madrid-Seville high-speed line in central Spain on Wednesday, with the Japanese government saying two of its nationals may have been aboard.

Spain's transport minister Oscar Puente said the accident occurred at 8:53 a.m. after a computer system malfunction automatically stopped six trains on the line and a rail control center told the driver of the following train to depart, despite a red signal, while the safety system was not functioning.

He called the control center decision a clear and inexplicable error but stopped short of saying it caused the crash.

In Tokyo on Thursday, Chief Cabinet Secretary Minoru Kihara told a press conference that Spanish authorities had notified Japan that the names of two Japanese nationals were on the passenger lists. Their safety was still being checked, he said.

Japan has set up a response headquarters at its embassy in Spain and a response office at the Foreign Ministry in Tokyo, according to the government.

Spanish newspaper El Pais reported that 107 people were injured, including 18 in critical condition.

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