The northern region of the Northern Marianas is calling for federal government help to stop illegal fishing in protected areas.
The Northern Islands mayor's office said vessels had been seen in the Marianas Trench Marine National Monument area that was established in 2009.
69760535 - scenery of the fishing port Photo: mtaira/123RF
The office's Kelly Tenorio said remnants of nets had also been recovered around the islands of Farallon de Pajaros, Maug, and Asuncion.
The monument protects 200,000 square kilometres of waters in the Mariana Archipelago.
Ms Tenorio said the Northern sanctuaries were constantly being raped and she's also concerned ships from Guam making trips to the islands could bring in invasive species.