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Update: Five employees suffered minor injuries in DeWitt explosion

DEWITT, Iowa -- Guardian Glass says the Saturday night explosion at the DeWitt plant involved natural gas.

Around 7 p.m. on Saturday, June 3, emergency crews were called to the plant in the city's industrial park for reports of an explosion. Guardian confirmed several employees were injured, but did not say how many or to what extent.

In an update released Sunday, the company said five employees required medical attention, but all were released from the hospital without serious injury.

"Our hearts go out to these employees and their families," the statement said. "We are grateful for the outpouring of support and are truly appreciative to be a part of the DeWitt community."

A Guardian spokesperson said the exact cause of the explosion is still under investigation, and the company is assessing the extent of the damage to the east side of the plant.

Employees are being told to not come into work until Guardian can ensure the plant is safe for operations.