The U.S. Forest Service employee accused of starting the largest wildfire in Colorado history was released Thursday on $600,000 bail.

As a condition of her release, Terry Barton, 38, will be required to stay at a halfway house and get mental health counseling. She is also not allowed to leave the state or enter a forest.

At a hearing, Barton quietly answered "yes" when asked if she understood the agreement.

Barton has pleaded innocent to four federal charges, including arson, for allegedly starting a 137,000-acre blaze that has destroyed at least 133 homes and cost more than $26 million to fight.

The 18-year Forest Service employee was indicted by a federal grand jury over the fire was started June 8. On Wednesday, Barton's estranged husband agreed to use their home as security for her bond.

Barton has allegedly told authorities she sparked the fire accidentally while burning a letter from her estranged husband.