SAN FRANCISCO (CBS SF) — A post office in San Francisco’s Sunset District has been evacuated after a substance spilled in the lobby caused people to experience irritation in their eyes, noses and throats, according to a fire official.

The spill was reported just before 5 p.m. at the post office at 1314 22nd Ave., according to Mindy Talmadge, a spokeswoman for the San Francisco Fire Department.

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The first firefighters on the scene reported that the unknown substance causes immediate throat irritation, and some customers are complaining of symptoms including watery eyes and itchy throats, Talmadge said.

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Medics are responding.

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