NASHVILLE, Tenn. (WKRN) — The Nashville International Airport (BNA) reportedly evacuated a number of people so they could get some fresh air following an incident involving a solvent inside one of the concourses.

BNA said the concourse was evacuated shortly before 2:45 p.m. on Sunday, April 16 because of “the presence of a noxious odor.”

Meanwhile, the Nashville Fire Department told News 2 that personnel were responding to Concourse C due to “something airborne causing breathing problems.”

Photos and videos shared with News 2 showed emergency responders gathering on the tarmak outside the concourse, as well as walking through the airport with masks and oxygen tanks.

“It was a strong odor,” Kyler Robinson, an airport employee, told News 2, describing the smell as similar to a pepper spray.

According to BNA, the fire department conducted air quality testing and determined there were no air contaminants.

The airport said crews also took chemical samples, which revealed the substance was Butoxyethyl Acetate, a solvent commonly used in lacquers, varnishes, enamels, and resins.

Fire officials said they do not have any patients at this time.

As of 4:35 p.m., BNA said Concourse C has reopened after it was deemed safe by the incident commander, but officials will continue to monitor the situation.

In addition, the FAA issued a ground stop to help the airport return to normal operations safely. However, at 4:50 p.m., BNA announced the ground stop has been lifted and flights are resuming.

Meanwhile, travelers are encouraged to check with the airlines about the flight status for arrivals and departures.

As of 5:55 p.m., Flight Aware reported 163 flights were delayed and six were canceled at BNA on Sunday.

There is still no word on how the solvent was spread around the concourse.