Several cars of the train were carrying ethanol, which is highly flammable. The train jumped the tracks at about 2 a.m. on the edge of the small town.
About 800 residents were affected. Bright orange flames and plumes of smoke could be seen for miles in the early morning hours.
The fires were under control Friday evening but have been very difficult to extinguish. Firefighters expect to strike those fires completely by Saturday.
The residents of Tiskilwa were evacuated after the initial blast. There was no need to make the evacuation mandatory because people heard the explosions, saw the fireball and knew it was time to get out of town.
The tank cars were carrying denatured alcohol, and so with the derailment on the edge of town, all the residents were asked to leave.
On Friday afternoon, residents were beginning to return to their homes.
The train itself is an Iowa Interstate freight train on the old Rock Island lines, with two locomotives, over 100 cars, 60 of them carrying the denatured alcohol, which is used for solvents, fuels, and is highly flammable.
Twenty six of the rail cars derailed. Seven of nine tanker cars telescoped into some grain cars at the front of the train. The tankers ruptured and there were multiple explosions, a huge fireball, and fumes in the air that were noticeable to some.
"The whole eastern sky was red, orange. It was very ominous. Nobody had to tell us to get out of town," said Stan Bensen.
The explosions bounced Richard Fisher out of bed.
"We looked up and there was a fireball as high as you wanted to see," said Fisher.
Around 2:30 a.m. Friday morning, people started going door to door evacuating residents. Residents quickly grabbed what they needed and left for friends, nearby motels or the high school in Princeton.
"I don't know what to think," said resident Lillian Stakely. "I've never had this happen...I forgot my [pills]," said Lillian Stakely.
Denatured alcohol, used in solvents and certain fuels, burns hot and fast, and an early reason for the voluntary evacuation was fear of foul air.
"I smelled something in the air. It was just kind of thick. I've never smelled that before," said Cynnandra Luttrell.
The air quickly cleared, but the fire didn't go out.
Photographer Jeff Freeman was allowed initially to get fairly close to the derailment site. As he passed by the train on an ATV, a relief valve on one of the tankers gave way, which indicated the tank car itself was quite hot.
The early plan was to let the fires burn themselves out, but with relief valves popping away, firefighters had to lay on water to cool and foam to extinguish.
Freight shipments of ethanol happen every day on this line, but residents say recent track work has been followed by faster moving trains.
"As we understand it, this is what we've been told, by repairing the tracks, they are able to increase their speed from 20 to 40 going through town, and it's too much," said Stan Bensen.
"Our house is 135-year-old, strong as everything house, but we feel it vibrating now when those tankers, filled tankers go through, so we notice a difference," said Marilea Bensen.
No town residents were injured.
The cause of the derailment is unknown. The National Transportation Safety Board is on site investigating.