Several participants in a soccer camp at Drew University fell ill while at a pool on the Madison, New Jersey campus Monday, but school officials say — contrary to some early media reports — there weren’t any heightened chlorine levels in the water.

Children ages 10 to 17 were affected, said Jeff Paul, director of the Morris County Office of Emergency Management, in an email to Gothamist. Some reported suffering shortness of breath, difficulty speaking between breaths, nausea and “general airway issues,” he said.

About a dozen were taken to Morristown Medical Center but had been released by late Monday afternoon, hospital spokeswoman Karen Zatorski said.

While Paul said officials responded shortly after noon to a report of juveniles falling ill “as a result of being exposed to a higher-than-normal concentration of liquid chlorine,” Drew officials disputed that statement.

“Initial tests detected normal levels of chlorine and all systems were working as expected,” Stuart Dezenhall, a university spokesman, said. Follow-up tests with Morris County Hazmat and Madison officials again showed no heightened chlorine levels, he said, adding that staff was working with local authorities to conduct further testing.

Paul said Madison police were handling the continuing investigation into chlorine levels, but added, “we responded to reports of chlorine related medical issues and that is what the symptoms supported.” Madison police haven’t yet returned a request for more information. Zatorski said she couldn’t speak to a root cause for the campers’ symptoms.

Dezenhall said the campers were taken to the hospital “in an abundance of caution,” and their parents or guardians were notified.

Paul said several local emergency agencies, including police, fire, first aid and EMS squads, responded to the incident, helping transport children to the hospital as needed. The county’s mass casualty response staff took part in the response as well.