LEEDS, Ala. (AP) - Several workers at an Alabama factory are being treated for injuries sustained when the roof collapsed Thursday morning.

Others had to be helped from the rubble of the M&B Hangers company in Leeds, near Birmingham. None of the injuries appears to be life-threatening.

About 40 people were inside the clothes hanger company when the roof fell in shortly after 9 Thursday morning.

About one-third of the roofing over the 100,000-square-foot building fell. It crashed into an area that has picnic tables and is used as a break area and for storage.

It's not clear what caused the collapse. The roof is flat and may have been weighted by heavy rain.

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