Jurors have been deliberating the case against Benjamin Gilmore for several days. Monday, the jury foreman told a judge that jurors were split. The judge responded by telling them to keep working.
The beekeeper and Occupy movement sympathizer had faced charges including arson and attempted murder after the fire in October destroyed a building under construction and spread to a residential complex next to it.
Investigators have said Gilmore's watch was found near where the fire started, and Gilmore had burns when he was arrested. Gilmore has said he lost his watch and had burned himself before the fire.
Prosecutors could decide to try Gilmore again, seek a plea agreement or drop charges.
(KUSA-TV © 2012 Multimedia Holdings Corporation with The Associated Press)