The train with 105 loaded cars - 103 of them carrying crude oil - derailed at approximately 1:20 p.m. CST (1920 GMT), according to a BNSF statement. The incident occurred on what appears to be a major rail line alongside the Mississippi River that handles as many as 50 oil-trains a week, one official said.

Local TV published images of dark smoke rising from the area where the incident occurred, and the Illinois Environmental Protection Agency told local WREX.com that initial reports suggested two of the cars were on fire.

The incident marks the latest in a series of derailments involving trains hauling crude oil, a trend that has put a heightened focus on rail safety.

A BNSF Railway train loaded with crude oil derailed on Thursday afternoon in a rural area south of Galena, Illinois, with two of the tank cars catching fire, according to local officials and the company.

BNSF said there were no reported injuries and no evacuations. The Berkshire Hathaway unit said it did not know what had caused the derailment, which occurred about 3 miles outside Galena, a town of just over 3,000 on the border with Wisconsin.

Eight cars derailed just before 2 p.m. central time, according to Galena City Administrator Mark Moran, six of which had tumbled onto their side.

The smoke could be seen as far as Galena, he said. Emergency responders have been called back to Galena as a precaution, and BNSF responders had taken over control of the site.

It was not immediately clear where the train originated or where it was heading. Chicago, which is 160 miles east, is a major rail hub for shipments from both North Dakota and Canada's oil sands.

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About 40 to 50 oil trains come through the area each week, Jo Daviess County Emergency Manager Charles Pedersen said. He had earlier said there was no explosion or fire at the site.

The accident is just the latest involving oil trains in the United States and Canada.

In 2013, 47 people were killed in the Quebec town of Lac-Mégantic after a train carrying crude oil derailed and exploded. The last incident was just three weeks ago.

Last month, a Canadian Pacific Railway freight train derailment in nearby Dubuque, Iowa, spilled ethanol fuel into the water and set three cars on fire. Dubuque, which is 14 miles to the north west of Galena, has almost 60,000 inhabitants.