JONESBORO, Ark. — Jonesboro fire crews are investigating a fire that broke out overnight in the downtown area. It happened just before midnight in the 400 block of Union Street. Witnesses say the flames were visible from two blocks away. Fire officials say several businesses are a total loss, and crews were still putting out hot spots around 6 a.m. Friday morning. No injuries have been reported at this time. The cause of the fire is unknown.