North Korea has fired multiple cruise missiles toward the Yellow Sea early Saturday.

South Korea’s Joint Chiefs of Staff said the missiles were launched at around 4 a.m., without providing further details of the launch. 

This comes two days after South Korea and the U.S. wrapped up their joint Ulchi Freedom Shield exercise, which the North calls a rehearsal for invasion. 

North Korea said earlier in March that it developed strategic cruise missiles, dubbed "Hwasal-1" and "Hwasal-2," claiming that they can carry miniaturized nuclear warheads.