Railroad officials say it's unclear how much ethanol has leaked into the Mississippi River following a train derailment in eastern Iowa, but that they're working to monitor the environmental impact and offload fuel from the train.
The cars went off the tracks Wednesday morning in a remote area about 10 miles north of Dubuque.
Canadian Pacific spokesman Jeremy Berry says eight of the 14 derailed cars carrying ethanol appear to be leaking. He says some ethanol has reached the river, but it's unclear how much.
Federal and state environmental agencies are working with Canadian Pacific to set up ethanol monitoring sites downriver.
Local authorities say three cars caught fire and three others plunged into the river. Fires from the accident had been extinguished by Thursday morning. No injuries were reported.