SEOUL, South Korea — Another North Korean soldier defected to South Korea on Thursday — and the South’s military fired warning shots as their northern counterparts approached the border, a South Korean military official said.

The defection came a little more than a month after a North Korean soldier defected in a dramatic flight in which he was shot by North Korean soldiers before being rescued by soldiers from the South.

The soldier on Thursday defected across the border at around 8:04 a.m. local time (6:04 p.m. Wednesday ET), the South Korean military official said. Later, North Korean soldiers looking for the defector approached the border, the official said.

"We responded by broadcasting warning messages and also fired 20 rounds of K-3 automatic rifle at around 9:30 a.m. as North Koreans came near the MDL," or military demarcation line, the South Korean military official told NBC News.

The official said that around 10:13 a.m., gunfire was heard from the North but there was no damage found in the South.

"Our military safely guided the defected solider and plans to investigate further the defection process and motivation," a spokesperson for the South Korean Joint Chiefs of Staff, Roh Jae-cheon, said at a news conference.

"Through our lookout equipment and security guards, we conducted the operation when the North Korean soldier clearly demonstrated his willingness for defection," Roh said.

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The South Korean news agency Yonhap reported that two other North Koreans also defected in a boat on Wednesday, citing the Unification Ministry. The boat was found by South Korea’s navy during a patrol and the men said they wanted to defect, Yonhap reported.

Yonhap reported that 15 North Koreans, including four soldiers, have fled to the South this year. One soldier and four civilians did the same in 2016, according to the news agency.

A North Korean soldier (C) takes pictures during the visit of Julie Bishop (not pictured), Australian Minister for Foreign Affairs, at the Military Demarcation Line in the Demilitarized Zone (DMZ) on Feb. 18, 2017 in the border village of Panmunjom, South Korea. Kim Hee-Chul / EPA file

North Korea, ruled by dictator Kim Jong Un, is an impoverished state ruled by a brutal totalitarian government. Tensions have escalated on the Korean peninsula as U.S. President Donald Trump has ratcheted up war rhetoric in response to threats and more sophisticated missile tests from the North.

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Most North Korean defectors undergo security questioning by South Korea's intelligence agency before being sent to a resettlement center for a three-month education on life in the country, Reuters reported after the Nov. 13 defection of the North Korean soldier, identified only by his family name Oh.

After they are released, central and local governments provide 7 million won ($6,450) in cash over a year, as well as support in housing, education and job training.

About 30,000 North Koreans have defected to South Korea, mostly via China, since the end of the 1950-53 Korean War, the Associated Press reported.

Stella Kim reported from Seoul, South Korea, and Phil Helsel from Los Angeles.