South Korea marines are set to conduct live-fire drills Tuesday on two islands near a tense maritime border with the Democratic People's Republic of Korea (DPRK), local media reported.

The one-day drills on front-line South Korean islands of Yeonpyeong and Baengnyeong will mobilize K-9 self-propelled howitzers, Vulcan cannons and 81-millimeter mortars and will be observed by ten U.S. military officials, according to Yonhap News Agency.

The exercises are part of the routine schedule, and there is no unusual move detected north of the border, officials told Yonhap.

The two Koreas exchanged fire off Yeonpyeong last November, leaving four South Koreans dead and prompting Seoul to work on building forces on five front-line islands in the Yellow Sea.

The tense Yellow Sea border was drawn at the end of the 1950-53 Korean War by the U.S.-led United Nations Command. South Korea and the DPRK have had several naval skirmishes near the border, which Pyongyang never officially acknowledged.