South and North Korea exchanged fire across the heavily fortified border on Sunday in the latest clash on the divided Korean Peninsula amid concerns that tensions could scuttle high-level talks between the two sides.

There were no reports of casualties or property damage in South Korea, though no details were immediately known about the situation in the North.

The incident occurred around 5:40 p.m. when South Korea, after broadcasting warning messages, fired warning shots against about 10 North Korean soldiers who were approaching the military demarcation line in Paju, said an official of South Korea's Joint Chiefs of Staff.

It was not immediately known what prompted the North Korean soldiers to try to advance toward the military demarcation line in Paju, a city located about 40 kilometers northwest of Seoul.

Earlier Sunday, South Korea had aired warning messages to the North Korean soldiers who were attempting to walk toward the military demarcation line, the official said.

After South Korea's warning shots, North Korea apparently fired back against South Korea, the official said, noting two marks from North Korean rounds were found in a South Korean guard post.

South Korea also returned fire against North Korea, the official said, adding that the exchange of fire lasted about 10 minutes.

The official said South Korea is closely monitoring the situation, though there was no unusual movement from North Korea's military.

The latest exchange of fire came hours after a senior presidential aide said in Seoul that he believes South and North Korea could hold the high-level talks as scheduled.

The two Koreas agreed to hold high-level talks between late October and early November during a recent surprise visit to South Korea by a high-powered North Korean delegation.

South Korea has proposed to hold the talks on Oct. 30 as North Korea asked the South to set a date. Still, the North has kept silent on Seoul's offer. 

"I hope the second high-level contact between the two Koreas will go off without a hitch and we are making preparations for it," Ju Chul-ki, senior presidential secretary for foreign affairs, told reporters without elaborating.

On Saturday, South Korea, after broadcasting warning messages, had fired warning shots against different North Korean soldiers who were approaching the military demarcation line in the eastern section of the border.

Still, there was no exchange of fire as North Korean soldiers pulled back without firing shots, according to the official.

Earlier this month, the rival Koreas also exchanged machine gun fire across the border after the North apparently tried to shoot down balloons carrying anti-Pyongyang leaflets.

North Korea has repeatedly pressed South Korea to keep activists and North Korean defectors from flying propaganda leaflets critical of North Korean leader Kim Jong-un.

Still, South Korea said there are no legal grounds to prevent its activists from floating the leaflets, citing freedom of expression.

(Yonhap)