So who or what did this? The Pennsylvania Fish & Boat Commission cannot say.By Meghan Schiller

UPPER ST. CLAIR, Pa. (KDKA) — People across two counties say they cannot believe their eyes or noses.

KDKA’s Meghan Schiller reports there is now an active investigation into thousands of dead fish. The stench of dead fish fills the air, attracting flies to Chartiers Creek.

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(Photo Credit: KDKA)

“I see one dead fish, two dead fish. … Then all of a sudden, there were dead fish everywhere. Just every fish in that creek was dead,” said Jake Conroy.

Big fish, small fish, he estimates in the thousands.

“I was fuming,” Conroy said. “Somebody has to be held responsible for this because Mother Nature didn’t do that.”

So who or what did this? The Pennsylvania Fish & Boat Commission cannot say.

“Sometimes, there is a pollutant in the water. Sometimes, there is a rapid change in temperature,” said spokesperson Mike Parker.

Officials believe the start of the “fish kill” is Chartiers Creek near Valley Brook Road. An investigation began Friday.

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“Water quality will be monitored, specimens will be taken from the stream to see if we can come up with any clues,” Parker said. “But at this point, we don’t exactly know what’s going on.”

In McKees Rocks, Andre Holmes saw dead fish dumping out of Chartiers Creek into the Ohio River.

“I have never seen anything like that outside of a horror movie. I was like OK, Stephen King-type of stuff here,” Holmes said.

But it is not fiction. And the reality is, the damage is done.

“I’m not an expert so I’m not pretending to be one. But I’ve been around the water long enough to know this is not a natural occurrence,” said Holmes.

KDKA’s Meghan Schiller as the Pennsylvania Fish & Boat Commission if it is a pollutant, could criminal charges be brought? Parker said if that happens, the person or company would face fines and likely try to settle out of court.

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If it’s something environmental causing the dead fish, we should hear when the investigation wraps up.

Meghan Schiller