Warships from the rival Koreas exchanged warning shots Tuesday after a North Korean ship briefly violated the disputed western sea boundary, a South Korean defense official said.

The shots were fired into the sea and there have been no reports of injuries and damage to the ships of either side, the official said on condition of anonymity, citing office policy.

Such exchanges are not uncommon at the sea boundary, the scene of several deadly maritime skirmishes between the Koreas in recent years. But the latest incident happened three days after a group of high-profile North Korean officials made a surprise visit to South Korea and agreed to resume senior-level talks.

South Korean President Park Geun-hye on Monday stressed the need to hold high-level talks on a regular basis, saying she hopes North Korea would show how sincere it is about improving ties.

The South Korean official said the North Korean ship was in South Korea-controlled waters for about 10 minutes before it retreated to its waters. He said a South Korea navy ship first broadcast a warning and then fired warning shots before the North Korean ship fired back at waters near the South Korean ship. The South Korean ship returned fire into the sea near the North Korean ship, the official said.

North Korean navy ships and fishing boats frequently violate the boundary drawn by the American-led U.N. command at the end of the Korean War in the early 1950s without the North's consent. The line cuts North Korea off from rich fishing waters.

The Korean Peninsula remains at a technical state of war because the Korean War ended with an armistice, not a peace treaty.