A dairy in northeast Iowa is under investigation for a manure spill.

The spill at the Denver Dairy was discovered by workers when they began work last Thursday morning. They initially reported that the manure had not reached a stream, but an unknown amount of manure did reach an underground tile line that flows into a tributary of Crane Creek about 12 miles north of Waterloo, Iowa, according to news reports.

It was unknown if the spill caused a fish kill.

The state Department of Natural Resources says it will issue a notice of violation for not reporting the spill within six hours of when it happened or was discovered.

Source: Waterloo Cedar Falls Courier and WHO-TV, Des Moines, Iowa