DETROIT (CBS DETROIT/ AP) — A suspected prank that injured two Detroit city workers Wednesday morning is under investigation.

Authorities say the men, ages 59 and 41, were injured after fireworks went off under toilet seats at a garage where fire equipment is repaired.

The men, who work in Detroit’s General Services Department and are not fire department workers, were treated at a local hospital for unspecified injuries.

A police report describes the fireworks as some type of “poppers” and says they were placed under at least one toilet seat. It says the victims sat down and set off the poppers.

No arrests have been made.

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