A popular pond in Boston's Jamaica Plain neighborhood is closed to water activities due to the suspected presence of cyanobacteria.
The Boston Public Health Commission announced Friday evening that Jamaica Pond appeared to be experiencing a harmful algae bloom.
"These blooms may produce toxins that can make people and pets sick," the commission said in a statement. "Park visitors are urged to avoid contact with the water and any areas of algae concentration, even on shore."
Visitors cannot swim, fish, boat or engage in any other activities on the water. Health officials say dogs should also not be allowed to swim in or drink the water.
"In the event that you, your child, or your dog comes in contact with the water or an algae bloom, rinse off immediately," the commission said.
Health officials could not say when the pond will reopen, but said testing of the water would be ongoing.