Medical wastes washing ashore at Assateague Island National Seashore have prompted a swimming closure/NPS file

Medical wastes washing ashore at Assateague Island National Seashore in Virginia and Maryland have led to a closure of all ocean-facing beaches to swimming or wading.

A park statement said the closure applies to North Beach, Oceanside Camping Beach, South Beach, the beach on the Oversand Vehicle Area and the Chincoteague Beach. 

All campgrounds, trails, boardwalks, and visitor centers remain open. Bayside remains open for kayaks, canoes and other water activities (at least for now).

The wastes, which include syringes and needles, started coming ashore Sunday morning, according to the statement. 

"We currently have no idea where it came from and will not be speculating about a source. Health authorities will be investigating," the statement posted on the park's social media channels said. "We do not know how long the closures will be in effect. We do not know how much more material is out there, when it will stop coming ashore, and how long it will take for cleanup."

The problem wasn't restricted to the national seashore, but ranged from Fenwick Island to Chincoteague in Virginia.