SEOUL, South Korea (AP) – North Korea’s navy on Monday accused South Korea of sending warships into its waters off the divided peninsula’s west coast, warning the South would face unspecified “consequences” if the alleged provocations continue.

The South’s Defense Ministry rejected the North’s accusation.

“We never violated the Northern Limit Line,” said a ministry official, referring to the U.N.-drawn sea border. The official spoke on condition of anonymity citing policy.

The North’s navy command claimed that the South’s “warlike forces infiltrated” warships into its territorial waters many times recently, according to a statement carried by the North’s Korean Central News Agency.

“If the South’s military ignores our warning and sticks to military provocations like this, it will be forced to take full responsibility for all consequences,” the North’s navy said.

It did not elaborate on what those “consequences” would be.

North Korea doesn’t recognize the current sea border demarcated by the United Nations at the end of the 1950-53 Korean War, and has long claimed it should be further south.

The waters around the border are rich fishing grounds and boats from the two Koreas routinely jostle for position during the May-June crab-catching season. In 1999 and 2002, their navies fought deadly skirmishes, killing several sailors and sinking six ships.

Earlier this month, the North’s navy issued a similar warning, saying that a similar skirmish could happen again at any time unless the South stops entering its waters.