Ripley volunteer firefighters were dispatched to Dawn and Gary Robinson's home at 114 Smith Drive No. 5 about 9:59 a.m. They cleared the scene about 10:38 a.m., firefighters said.
The couple and a relative were in the home at teh time, but escaped the flames unharmed, and were waiting outside as firefighters arrived.
Three witnesses reported seeing smoke and sparks coming from the bedroom ceiling light fixture prior to the fire department being called.
County fire investigator Martin Henderson said he found evidence of a charred fixture, but the age of the mobile home (over 35 years) along with the bedroom mattress contributed to the intensity of the fire.
"The investigation is still ongoing, but preliminary evidence suggests the cause of the fire is accidental with the most likely source of ignition being electrial," Henderson said.