Earlier this week, North Korea banned ships from entering the area off its east coast. According to South Korea, the goal is to launch missiles or test other weapons by North Korea, but so far no tests have been carried out there.
South Korean news agency Yonhap quoted an unnamed military source as saying that the warning for the northeastern part of North Korea's east coast was targeted Sunday through Monday.
"Such warnings are usually designed to prevent ships from approaching areas on the eve of missile launches or other weapons tests," the news agency said.
"Seoul General Staff officials said there was no ballistic missile or artillery attack in the area during this period," the statement said.
South Korean newspaper Joongang Ilbo also reported that North Korea had warned ships and that Pyongyang might try to launch a missile on Sunday, but did not provide any further details.
VOA has not received any warnings or information to support a possible testing attempt. A spokesman for the South Korean Ministry of National Defense told Voice of America in a written statement that North Korea is conducting summer military exercises. "South Korean and American intelligence are closely monitoring the situation," the statement said.

Royal