The accidental derailing of six cars of a freight train forced thousands of people to evacuate homes, businesses and a nursing home within one mile of the wreck Saturday in Lafayette, Louisiana. What happened actually was that the wreck caused a hydrochloric acid leak, which forced people do so.

Lafayette Parish sheriff's Lt. Craig Stansbury told that the spilled acid sent a toxic cloud over the area, and at least five people, including two railroad workers, were taken to a hospital and treated after complaining of skin and eye irritation.

Dr. Jimmy Guidry the state health officer reported that a nursing home with 161 residents was evacuated, and about 35 of the residents deemed too frail to travel were taken to area hospitals, he said.

Stansbury told that police walked door-to-door notifying residents of the mandatory evacuation in an area with an estimated population of 3,500 people. He said, "We're advising them to take enough supplies for approximately 48 hours."

Rodney Mallett, a spokesman with the Louisiana Department of Environmental Quality told that the train cars were carrying ethylene oxide, which is used in agricultural products and as a sterilizer for medical supplies. According to Mallett, BNSF was using lime to neutralize the hydrochloric acid. Cleanup workers will then either dig or vacuum up the acid and lift the cars back onto the track.

According to Joe Faust, a spokesman for the Texas-based BNSF Railway that operated the train involved in the spill, an estimated 8,000 to 10,000 gallons of the acid was spilled, he said. The acid formed a yellowish pool at the site of the derailment. Hydrochloric acid can cause respiratory problems and skin and eye irritation. However, Faust did not speculate on how long the cleanup might take but said residents wouldn't be allowed back into the area until officials were certain the hazardous material was gone. Faust said, "We want to make sure that they're not returning home prematurely. We want to make sure the entire area is clean."

Shelter manager Jacqui Picard  reported that The Red Cross has set up a shelter at a high school and was gearing up to handle as many as 500 people if possible.