Firefighters are still battling a blaze at a Nebraska biofuels plant after an explosion and haven't been able to get inside to search for three missing people. Fremont Mayor Joey Spellerberg says the fire at Horizon Biofuels has been burning since Tuesday. Firefighters have struggled to get close due to heavy smoke and flames. The explosion damaged the facility's tower, leaving debris scattered. The plant produces animal bedding and wood pellets. Fremont Fire Chief Todd Bernt says the facility stores wood and alcohol-based materials. Fremont is a city of about 27,000 people, northwest of Omaha.