MONROVIA ( — A chemical spill in Monrovia Monday sickened more than 50 people, nine of whom had to be taken to the hospital for treatment.

The spill, which reportedly took place at 11 a.m. at an air conditioning company in the 100 block of Railroad Avenue, gave off a “toxic vapor” and sickened more than 50 people, authorities said.

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About 200 people from the business where the spill occurred and another business next door were exposed to fumes that apparently entered a ventilation system, and some of them reported feeling dizzy, Monrovia city spokeswoman Alexis Newell said.

Nine people were taken to hospitals for treatment and 45 others were treated at the scene, she said.

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No evacuations have been ordered, but Newell said neighboring residents and employees were asked to shelter in place while crews worked to handle the problem.

Officials were working to determine what chemical was involved.

Officials from the South Coast Air Quality Management District were notified.

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