North Korea appears to have deployed a second corvette-class warship to an east coast port near the inter-Korean border during the recent joint U.S.-South Korea naval exercises in the East Sea.

NK News, a media outlet specializing in North Korea, issued the report Friday, citing satellite imagery from Planet Labs.

The images reportedly showed that a 15-hundred-ton Tuman-class corvette arrived at Goseong Port from a naval base in Munchon on October 30 and was docked alongside an existing 15-hundred-ton Amnok-class corvette until November 9. 

NK News reported that one of the vessels was no longer visible at the port on November 11, the first day of the joint exercises, suggesting it may have been conducting maritime operations.

The report said Pyongyang may have been sailing the ships to coincide with the joint drills to demonstrate its resolve and show it was ready to launch missiles if the allied fleets attacked.