NEW YORK -- A hazardous materials situation forced the evacuation of the National September 11 Memorial and Museum on Sunday afternoon, according to the New York police department.
NYPD officials confirmed to CBS News that an excess of chemicals used to kill algae in the memorial's reflection pools triggered a strong chlorine odor.
As CBS New York reported, police and firefighters evacuated the plaza for two hours as a precaution while the city's Department of Environmental Protection tested the water.
"Suddenly, my throat started burning and I sat down and drank my water," visitor Maria Hollowell told the station.
The NYPD said no injuries were reported.
Dr. Michael Caldwell, the former Health Commissioner for New York's Dutchess County, lives nearby.
"When it gets too much, especially on a hot day like today, it probably aerosolized, so there have been more coming off in the air," Caldwell explained to CBS New York. "And with a bunch of people here on a Sunday, there are more people being affected."
A spokesperson for the 9/11 Memorial said rain Saturday night exacerbated the problem but emphasized that it did not pose a health risk.