Two were carrying hazardous materials, but they did not leak after the accident around 5 a.m. in Bartlett. No one was injured and no homes were evacuated.
Three of the cars that derailed caught fire, and even though fire crews poured water on them for hours, they stubbornly kept burning into the afternoon.
"One contained a fire board material, one carried scrap metal and the third that was on fire was an empty car," said Mike Falese, Barlett fire chief.
Several tankers on the Canadian National train were carrying potentially dangerous chemicals, including ferrous sulfate, sodium hydroxide solution and organic acid. But those cars did not catch fire.
The derailment was causing major problems for commuters on Metra's Milwaukee West Line into Thursday evening. The wreckage may not be cleared until sometime Friday. Metra is telling most Milwaukee West commuters to find alternate transportation.
Emergency and hazmat crews were on the scene between Bartlett and Elgin since 5:30 a.m.
Pat Karolasz lives in Spring Lakes Estates, a stone's throw from the derailment. She was shaken from sleep by the boom at 5:30 Thursday morning and then saw the glow of fire.
"You're close. Yes, right here, right here. In the winter time you can see the rail cars," said Karolasz.
Amy Winters' townhome in the Castle Creek subdivision backs up to the track. She and her family saw flames, so they packed a few bags just in case they were asked to evacuate.
"This has always been our worst nightmare, something like this happening, since we're so close, and it's happening," said Winters. "We saw the fire. It was just really high. We thought maybe the surrounding buildings were on fire. We didn't know what to make of it."
Winters and her neighbors are aware of the increased number of freights on the CN, and more broad-based concern that more trains presents a greater risk of derailments.
"Right now we're in a response mode. We want to conduct a thourough investigation and get these rail lines re-opened," said Patrick Waldron, CN spokesman.
Some cars of the Canadian National freight train caught fire and were reported off the tracks near Gifford and New Spaulding roads about a half mile from the Winters' subdivision. A company spokesperson says only one train was involved. So far, there are no reports of injuries or any toxic leaks.
Canadian National acquired the rail three years ago. Since then, worried neighbors like Danette Dudek say the traffic on the track went from about two trains a day to more than a dozen.
"They come barreling through," Dudek said. "The house shakes a little bit when there's heavy freight, so there's always been, in the back of my mind, of 'Gosh, what if something does come off the track?'"
Canadian National uses a 198-mile loop that runs through Barrington and other suburbs to skirt rail congestion in Chicago. In 2008, protestors rallied against the acquisition, saying it would scare business and development away from their communities. Winters said she is now more scared than ever.
"We are so close," she said. "Our cars are right underneath."
Milwaukee West Line Metra trains were halted in both directions between Big Timber and Elgin. Bus service was available between Roselle and Big Timber.
The Milwaukee West Line, which shuttles 12,000 passengers daily, is likely shut down until Friday.
"Most of our trains come out of a yard in Elgin, and they can't get past this accident. So we had a couple trains on the other side of the accident that we've been using to operate a very limited service this morning. We've been advising all our riders to use alternative transportation. If the UP West or UP Northwest works for them, the North Central service line shares these tracks further in downtown from River Grove on in, so if they can use North central service, they should do that. But as of now, we do not expect this line to be restored to normal service until at least tomorrow," said Mike Gillis, Metra.
Officials say they do not know what caused the derailment.
Media choppers were asked to avoid the scene because of possible hazardous fumes concerns early Thursday.
New Spaulding and Gifford were shut down in the area. Bartlett Road was closed from Naperville Rd. to just east of Route 25.
Crews from Elgin, Bartlett, Streamwood and West Chicago responded to the incident.
U46 school district has put out a rapid notification phone call to all 41,000 parents of students that attend U46, notifying them of the incident and that transportation across the district could be delayed. There are 370 buses that travel the district each morning. U46 was not sure how routes are affected.
North Central Metra service is not affected.