Six cars of a freight train derailed Saturday, causing a hydrochloric acid leak that forced thousands of people to leave homes, businesses and a nursing home within one mile of the wreck.

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, said Lafayette Parish sheriff's Lt. Craig Stansbury.

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

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

Mona Hebert and Jeffrey Ferrara said they were rousted from their trailer around 3:45 a.m. and told they had two minutes to leave. Ferrara, who lost his home in Hurricane Katrina and has been staying with friends like Hebert since then, didn't have time to grab his shoes or any of his medications.

"This is gravy compared to" Katrina, Ferrara said, adding that the morning air smelled of chlorine, like a swimming pool.

Hydrochloric acid can cause respiratory problems and skin and eye irritation, 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.

A train car carrying ethylene oxide, used in agricultural products and as a sterilizer for medical supplies, was overturned but was not leaking, said Rodney Mallett, a spokesman with the Louisiana Department of Environmental Quality. Continued...