Dutch rescuers recovered the body of one maintenance worker Monday and labored round the clock to find four others who fell into a 260-foot-high steam boiler at a power plant.

Eight men — four Turks and four Americans — fell into the industrial boiler when their 230-foot-high scaffolding collapsed while they were cleaning an inside wall on Sunday.

Two Americans and a Turkish man were rescued the same day, two of them through holes drilled in the boiler at a height of 65 feet, said Frits Slootmans, spokesman for the city of Geertruidenberg (search).

A fourth man was dead by the time the firemen reached him on Monday. His nationality was not released.

Four other maintenance workers were believed trapped or buried at the bottom of the boiler under the pipes and platforms that rained down on them, Slootmans said. The scaffolding buckled to a height of around 150 feet. The cause of the collapse was not known.

"This is a very complicated operation and could take up to a week," Slootmans said. "We fear they may not survive."

The eight men were working in two teams on scaffolding constructed on the inside of the towering boiler, which was shut down a month ago in preparation for the cleanup.

Slootmans said the two rescued Americans were in "good condition and recovering" on Monday. The unidentified men are both in their 40s.

They were part of a crew of specialists hired specifically for the job, Slootmans said.

The Amercentrale (search) electricity plant, 60 miles south of Amsterdam, supplies power to millions of households.