COLUMBUS, Ohio (WCMH) — The findings of an investigation into what caused 240,000 AEP customers to lose power for several days during a June heatwave are set to be released Thursday.

PJM, the company responsible for routing electricity transmissions across 13 states, will reveal the findings of its months-long probe into June’s widespread power outages in central Ohio.

Customers lost power, some for several days, after severe storms with high winds ripped through the area the week of June 12. A heat wave with temperatures reaching into the upper 90s only made matters worse.

AEP Ohio said it was forced to cut power to some customers to prevent an overload to its electric grid, a decision officials said came directly from PJM.