RALEIGH, N.C. (AP) — Federal authorities have launched a criminal investigation into a massive coal ash spill into the Dan River.

The U.S. Attorney's Office in Raleigh issued a grand jury subpoenas demanding records from Duke Energy and the North Carolina Department of Environment and Natural Resources. The subpoenas seek emails, memos and reports from 2010 through the Feb. 2 spill.

The Associated Press obtained a copy on Thursday of the subpoena issued to the state. A Duke spokesman confirmed the company had also received one.

The spill at a Duke Energy plant in Eden spewed enough toxic sludge into the river to fill 73 Olympic-sized pools. It was the third-largest coal ash spill in U.S. history.

Prosecutors ordered the state environmental agency's chief lawyer to appear next month before a grand jury.


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