Toxic blue-green algae has been detected in Tallinn's Harku Lake after water samples were tested by the Health Board (Terviseamet).
Deputy elder of Tallinn's Haabersti city district Oleg Siljanov said that the test results showed that there was a moderate amount of toxic blue-green algae.
"Because of blue-green algae, swimming in Harku Lake is not recommended and a yellow flag has been hoisted," Siljanov said.
If people are exposed to blue-green algae for a long period of time it can cause serious health side effects, especially if the water is swallowed. It is most dangerous to children and old people.
Symptoms may include abdominal pain, diarrhea, vomiting, mouth ulcers, dry cough and headache.
Editor: Helen Wright