South Korea's military says North Korea fired cruise missiles eastward on Wednesday, as US and South Korean forces have been conducting regular joint military exercises over a number of days.

South Korea's Joint Chiefs of Staff said the missiles were launched near Hamhung in South Hamgyong Province at around 10:15 a.m. local time on Wednesday.

The South Korean military is working with its US counterpart to figure out the type of missiles, their ranges and other details.

US and South Korean forces began their Freedom Shield exercises on March 13. The drills simulate a contingency on the Korean Peninsula and are due to continue through Thursday.

In an apparent protest, Pyongyang launched an ICBM-class Hwasong-17 missile last Thursday.

South Korea's Yonhap News Agency reported that the latest launch by the North appears to be a part of continued protests against the joint exercise.

North Korea had said it test-fired four Hwasal-2 strategic cruise missiles on February 23 and two strategic cruise missiles from a submarine on March 12.