SHIRLEY - The gas leak that forced the evacuation of 900 Suffolk County homes has been contained, officials confirm.

Suffolk County Executive Steve Levy says a propane delivery driver discovered a broken valve in a 30,000-gallon tank near the Kohl's department store on Montauk Highway before 1:30 a.m. He says the underground tank may have been about half-full at the time.

Levy says residents who live in northern and eastern neighborhoods of the leak have been driving themselves out, while those without transportation are being driven out of the area by police and fire departments.

Stretches of Sunrise Highway, Montauk Highway and some other major roadways have been shut down. The Long Island Rail Road also suspended service between Speonk and Patchogue.

Levy says the evacuations are a precaution and that the disruption could last into Sunday. Nearly 20 fire departments and other agencies were at the shopping center throughout the day working to close the main valve.

The Red Cross set up a shelter at William Floyd High School where they say about 150 people have taken refuge.

Authorities say it is unclear when residents will be able to return to their homes.

This story was written with Associated Press wire reports.

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