Updated

The federal government has closed part of the Gulf of Mexico to royal red shrimping after a commercial shrimper found tar balls in his net.

In a news release late Wednesday, the National Oceanic and Atmospheric Administration says the new restriction covers 4,213 square miles of federal waters off Louisiana, Mississippi and Alabama and only applies to royal red shrimping.

NOAA says the Coast Guard is analyzing the tar balls caught by the shrimper to determine if they came from oil spilled after the April 20 Deepwater Horizon rig explosion.

Royal red shrimp are caught by dragging nets across the bottom of the seafloor. NOAA says fishing is still allowed in shallow waters in the area.