According to CBS DFW, the brothers, ages 11 and 12, were in a heavily wooded area of the park when they were electrocuted by the downed power line.
Another child who was with the brothers went to find help after the accident.
Firefighters believe the power line was downed during heavy storms that passed through the area roughly 12 hour before the accident. They said the lines may have been hidden by overgrown brush.
Fire fighters want to remind the community that all downed lines should be treated as if they are energized.