The Viktor Leonov has patrolled international waters flanking Florida, Georgia, and South Carolina, every year since 2014, but since its arrival this week, it has sailed with no warning lights and ignored other ships, the US Coast Guard said in a marine safety information bulletin, according to CNN.

"The United States Coast Guard has received reports indicating that the RFN Viktor Leonov (AGI-175) has been operating in an unsafe manner off the coast of South Carolina and Georgia," the notice said.


"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."

(U.S. Coast Guard photo by Petty Officer 3rd Class Charles Mark Barney)

The notice warned local vessels to steer clear, advising they "maintain a sharp lookout and use extreme caution when navigating in proximity to this vessel."

The US Navy destroyer USS Mahan is patrolling in the same area, an unnamed defense official told CNN.

It is entirely normal for Russian surveillance ships to patrol international waters near US Naval outposts like Naval Station Norfolk, Virginia, Naval Station Mayport, Florida, and Naval Submarine Base Kings Bay, Georgia, but the erratic behavior of the Viktor Leonov is not.

"We are aware of Russia's naval activities, including the deployment of intelligence collection ships in the region," a US Northern Command spokesperson told The Washington Times.

USS Mahan steams in company with USS George Washington in the Atlantic Ocean during Exercise Mediterranean Shark.

(U.S. Navy photo by Photographer's Mate Airman Rex Nelson)

The 3,800-ton Viktor Leonov was built in Poland, and began active duty in 1995 with the Russian Navy's Northern Fleet, according to Russia state news agency TASS.

The Viktor Leonov previously caught unwanted attention in January 2018, when it was spotted near an easterly US Naval base.

At the time the US Navy spokeswoman told Business Insider: "We are aware of the vessel's presence. It has not entered US territorial waters."

This article originally appeared on Business Insider. Follow @BusinessInsider on Twitter.