Two Russian Navy ships fired four cruise missiles into Syria from the Eastern Mediterranean on Tuesday, U.S. defense officials confirmed to USNI News.

A Kilo-class submarine and the Admiral Grigorovich-class guided missile frigate Admiral Essen launched four Kalibr NK SS-N-30A cruise missiles around 1:30 A.M. EST on Tuesday into Syria, a defense official said. A statement from the Russian Ministry of Defense identified the Kilo attack boat as Krasnodar.

Russian officials said the missiles were fired on ISIS positions near Palmyra in the middle of the country. The Russians claimed the targets were vehicles and heavy weapons ISIS moved out of the stronghold of Raqqa.

“[The ships] targeted an area east of Palmyra, where the militants’ heavy weaponry and manpower were located. The militants moved there from Raqqa. All targets have been destroyed,” read a statement from the Russian MoD.

Admiral Essen entered the Eastern Mediterranian earlier this month and operating with teh frigate Admiral Grigorovich, according to press reports.

U.S., Turkish and Israeli forces, “were informed in a timely manner of the missile launches through existing communication channels,” according to the Russian MoD statement.

The latest strike follows a November Kalibr launch from the Russian frigate Admiral Grigorovich that hits targets outside Aleppo.

The subsonic Kalibr missile has similar characteristics and ranges as the U.S. Tomahawk Land Attack Missile (TLAM).

The missile made its first combat appearance in 2015 when Russian warships launched 26 of the missiles on routes more than 900 miles long to strike targets in Syria and Iraq from the Caspian Sea.