PEOSTA, Iowa (AP) — State environment officials say a fish kill in northeastern Iowa was caused by farm manure runoff. The Iowa Department of Natural Resources says in a news release that it is investigating the Dubuque County fish kill near Peosta. Investigators say more than 200 fish were killed by the runoff, which they traced to Lawler Dairy farm in Peosta.

The agency says the farm applied liquid manure to a nearby field, and melting snow and rain caused it to run off into an unnamed creek that leads to the Little Maquoketa River.

Officials say charges are pending against the dairy.