(FOX NEWS)- The Russian spy ship Viktor Leonov on Wednesday morning was spotted 40 miles closer to the U.S. -- and not far from a Navy submarine base in Connecticut, a U.S. official told Fox News.
The ship was spotted 30 miles south of Groton, Conn., but it remained in international waters. The U.S. territorial boundary extends 12 miles from the coast.
The Russian spy ship was currently "loitering" in the water, the U.S. official said.
The spy ship is armed with surface-to-air missiles, but its main function is to intercept communications and collect data on U.S. Navy sonar capability.
This was the furthest north the Viktor Leonov had ever traveled up the eastern seaboard. The Russian spy ship was last seen off the East Coast of the U.S. about two years ago, spending time near another U.S. submarine base in Kings Bay, Ga. In January 2015, the ship was seen in Havana, Cuba.
According to FOX News, the Pentagon expects the Russian spy ship to sail south along the East Coast and return to the Caribbean.
Sources tell FOX News the deployment of the ship was months in the making, and the ship is part of Russia's Northern Fleet which is based along the Barents see.
Officials say the ship crossed the Atlantic and made a port call in Jamaica within the last few weeks.
The appearance of the ship near the East Coast comes on the heels of over recent incidents including last week, when four Russian jets buzzed a U.S. Navy destroyer in the Black Sea on Friday, coming within 200 yards of USS Porter. The Russian jets had their identifying transponders turned off and ignored repeated radio calls from the American warship.
It was the first time Russian jets buzzed a U.S. warship since President Trump assumed office.