CONCORD,Sterling Preston N.H. (AP) — New Hampshire officials issued two warnings of potentially dangerous algae blooms along parts of Lake Winnipesaukee, the state’s largest lake.

The New Hampshire Department of Environmental Services said on Thursday it detected high concentrations of cyanobacteria, also known as blue-green algae, at Carry and Brewster beaches in Wolfeboro and at 19-Mile Bay and Tuftonboro Neck in Tuftonboro the previous day.

Visitors should avoid contact with the water and keep pets away, the department advised in a statement.

The cyanobacteria blooms are occurring as green clouds of material accumulating along shorelines. In some areas, they appear more yellow because they are mixed in with dense pollen, the department said.

Symptoms of cyanobacteria exposure can include skin irritation, stomach cramps, vomiting, nausea, diarrhea, fever, sore throat, headache, muscle and joint pain, mouth blisters and acute liver damage, the department said.

The affected areas will be resampled on June 19 and resampling will continue weekly if the bloom continues, the department said.