The Commonwealth of the Northern Marianas is blaming tourists for human waste left on the shores of its beaches and tourist sites.
Staff from the islands' Bureau of Environmental and Coastal Quality found a trail of faeces during water sampling on the beaches.
They discovered the human waste in caves and scattered along the shore.
The Bureau said it's sure that visitors are responsible because beaches like Saipan's Hidden Beach and Jeffrey's Beach are frequented by tourists.
The authorities want to enforce tour guides' certification so they take responsibility for the tourists they take around the islands.