Passengers on board a Delta flight from Detroit to Chicago were quarantined on the tarmac for several hours this afternoon over concerns about one traveler with what appeared to be a mysterious rash.

According CBS Chicago, the rash was ultimately determined to be the result of bug bites, but only after the plane was surrounded by Chicago fire department trucks on the tarmac at Midway airport.

Passengers Tweeted photos of emergency responders seen below and here boarding the plane wearing hospital scrubs and face masks.

One person on the plane told CBS “there was a good amount of panic and disbelief,” before passengers were ultimately allowed to get off the plane.

CBS reports that the passenger with the bug bites may have originally flown to the U.S. from Ghana. The Centers For Disease Control are investigating the matter.

Still in quarantine. They say it’s not serious…pff twitter.com/KMaree_Sanders…

— Kayla Maree Sanders (@KMaree_Sanders) April 26, 2012

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