Nearly 2,500 people were forced to leave their homes after a toxic cloud took over the area. On Saturday, a tank from a chemical plant in Pennsylvania released a corrosive liquid which caused about three residents to have some serious respiratory problems. The liquid, called oleum, is similar to sulfuric acid and leaked from a tank at the Indspec Chemical Corp. plant in Petrolia, western Pennsylvania at 40 miles Pittsburgh.

Freda Tarbell, spokeswoman for the state Department of Environmental Protection, stated that the officials were very concerned about the health problems this leak can produce. Oleum can cause respiratory problems and burns. The authorities managed to announce the 2,500 residents who were living on a 3 miles area far from the leaking point.

Tarbell added that the authorities will check the air during the night and the residents will be allowed to return to their homes on Sunday morning. 250 of the residents went to shelters in Karns City, North Washington and Bruin but the Red Cross staff said it had room for only 50 or 100 people.

The chemical plant in Petrolia produces a bonding agent for the tire industry and all of the 30 employees working there were evacuated. No injuries were later reported. Only three of the residents were taken to the hospital after they had suffered respiratory problems. The toxic cloud was moving west on Saturday night, close to the ground, but no further evacutions were schedueld.

Still, many of the residents who were allowed to remain at home were also adviced to stay indoors and close the windows and shut any ventilation system.