YOUNGSTOWN, Ohio - Investigators now say it was a lack of oxygen that killed hundreds of fish at a pond in Mill Creek Park.

Officials at Mill Creek Park found the dead fish floating on the Lily Pond over the weekend. Wildlife experts now confirm that the fish kill was due to oxygen depletion after many days of temperatures hovering around 90 degrees.

Youngstown Soil and water Conservation, the Ohio Department of Natural Resources and the Environmental Protection Agency were called to investigate the incident. 

 Mill Creek Park officials are asking  the public to avoid the Lily Pond area until the environment returns to normal.