ORLANDO, Fla. -- Two monorail trains crashed early Sunday morning in the Magic Kingdom section of Walt Disney World, killing one train's operator, emergency officials said.

The monorail operator died at the scene of the crash, which happened around 2 a.m., said Bo Jones, deputy chief for Reedy Creek Fire Department. The other train operator was not injured, but was taken to a hospital because he was emotionally shaken. Five park guests were treated at the scene.

It is unclear what caused the crash, Jones said. Orange County Sheriff's officials are investigating the cause.

Jones said the crash happened at the park's ticket and transportation center. About a dozen guards wearing blue Disney security uniforms guarded the monorail station Sunday morning and prevented visitors from approaching the area.

Ethan Meus, who was visiting the theme park from Dubuque, Iowa, said he and his family took the monorail to dinner at a resort hotel Saturday night. Meus, 17, watched the Magic Kingdom fireworks from the monorail on the way back to his hotel, he said, and didn't notice any problems with the train.

"It's pretty shocking to hear that a driver was killed in that accident," Meus said.

The family was planning to take the train again Sunday to visit Disney's Epcot Center, but now planned to take a bus, Meus added.

"You would think it would be so safe," said 20-year-old Lauren Shoebottom, who was visiting the park from London. "You don't expect it on holiday, do you?"

Walt Disney World vice president of public affairs Mike Griffin issued a statement offering condolences to the employee's family and saying the monorail was closed.

"It's a bit shocking," said 22-year-old Danielle Williams, of London. "Disney seems so perfect."

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