The Coast Guard has warned boaters in Florida, South Carolina and Georgia that a Russian spy ship is operating in an “unsafe manner” along the Southeast coast. The agency said it has received multiple reports that the RFN Viktor Leonov, a surveillance ship, is operating erratically in international waters managed by Coast Guard Sector Jacksonville, which also covers the ports of Charleston, S.C., and Savannah, Ga.

“We are aware of Russia’s naval activities, including the deployment of intelligence collection ships in the region,” a U.S. Northern Command spokesperson told The Washington Times. “While we won’t discuss specific measures being taken, NORAD and USNORTHCOM routinely conduct air and maritime operations to ensure the defense of the United States and Canada.”

CNN reported that the Russian ship is being shadowed by the Norfolk, Va.-based guided-missile destroyer USS Mahan. The Russian Federation Navy traditionally monitors the U.S. coast. The U.S. Naval Institute said Russian ships have monitored Naval bases along the East Coast, including Naval Station Norfolk, Naval Station Mayport, Fla., and the nuclear submarine base at Kings Bay, Ga. The Viktor Leonov has come to the U.S. coast annually since 2015, according to CNN.

“This unsafe operation includes not energizing running lights while in reduced visibility conditions, not responding to hails by commercial vessels attempting to coordinate safe passage and other erratic movements,” the Coast Guard said in a bulletin issued Monday.

The Coast Guard warned boaters to use “extreme caution” in the vicinity of the ship. Mariners are asked to report any unsafe conduct by the Leonov.