CLARKSBORO, N.J. (AP) — More New Jersey residents were ordered Tuesday to leave their homes because of air contamination from a train derailment last week that leaked a hazardous gas.

The evacuation order imposed by officials at 4 p.m. added 100 more homes to the area of Paulsboro where people were not being allowed to stay, increasing the number of evacuated residences to more than 200.

The evacuation is expected to last until Sunday, a day longer than previously expected. Also, schools in Paulsboro are to remain closed until next week.

But Coast Guard Capt. Kathy Moore, a spokeswoman for the group of federal, state and local agencies managing the disaster response, said at a news conference in neighboring Clarksboro that the expanded evacuation means that others in Paulsboro will no longer have to stay inside.

The southeast New Jersey industrial town near Philadelphia has about 6,000 residents.

Friday, seven train cars derailed at an old railroad bridge over Mantua Creek; one tanker car ruptured, releasing thousands of gallons of vinyl chloride into the atmosphere. Though no serious injuries or illnesses have been attributed to the leak, dozens of people who live or work nearby were checked out at a hospital emergency room.

Exposure to vinyl chloride for short periods can cause dizziness, breathing problems and other symptoms. Long-term exposure to high levels has been linked to cancer.

Moore said the Coast Guard and other agencies hope to get the remaining 600 to 800 gallons of vinyl chloride out of the breached tanker car by Sunday by dissolving it into a liquid and pumping it out.

Since Friday, the evacuation area was expanded and residents of the entire community were told to shelter in place and keep their windows shut. The latest shelter-in-place order was lifted Tuesday after about 22 hours in effect. But on a day with temperatures over 60 degrees, many people in town were out walking.

Conrail, which owns the rail line, is paying for hotel rooms, meals and other expenses for residents who cannot stay in their homes. A company spokesman said 100 more hotel rooms were reserved for people being told to get out.

A gym at Kingsway High School in Woolwich has also been set up as a shelter, though it was not clear how many people might need it.

National Transportation Safety Board inspectors have been staying away from the accident site until the hazardous material is removed.

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