Fire broke out in the control room of the world's tallest observation wheel Tuesday, trapping 173 people hundreds of feet above the ground for hours and forcing rescuers to lower 10 passengers to safety by rope.

Two passengers were hospitalized with minor ailments.

During the six hour ordeal, passengers were able to talk with officials via intercom and rescuers tethered to harnesses brought them sandwiches and soft drinks, said general manager Steven Yeo.

"It took a while," Yeo said. "Some of them were a bit disturbed."

The 541-foot Flyer, which has carried 2 million passengers so far, is about 100 feet taller than the London Eye, formerly the world's tallest observation wheel. It was built by Japan's Mitsubishi Heavy Industries.

Technicians were able to get the wheel moving again a little more than six hours after it ground to a halt and most of the passengers exited normally, Yeo said.

The wheel, known as the Singapore Flyer, has stalled twice before for about an hour each time since it began operating in February.

"This is the first time that something of this nature has happened, where people were hospitalized," Yeo said.

A 70-year-old woman complaining of dizziness and a 10-year-old boy who vomited were taken by ambulance to a hospital, Civil Defense Colonel N Subhas said.

The 10 passengers closest to the ground were evacuated by harnesses attached to ropes, and civil defense rescuers were planning to bring the rest of the passengers to safety the same way when the wheel's power was restored, Subhas said.

The Flyer was to shut down for at least one day to allow for repairs and an investigation, Yeo said.