The Democratic People's Republic of Korea (DPRK) fired 10 rounds from multiple rocket launchers off its west coast on Monday, after a Republic of Korea (ROK) warship "invaded" the Military Demarcation Line and fired warning shots, state media KCNA said.

The DPRK opened fire at around 5:15 a.m. in response to ROK shots at around 3:50 a.m., a DPRK Army General Staff spokesman said.

The ROK's Joint Chiefs of Staff said that it had warded off a DPRK merchant vessel that had crossed the Northern Limit Line (NLL).

(With input from Reuters)