North Korea
A subway worker walks away after a train departed the station in central Pyongyang, North Korea May 7, 2016. Damir Sagolj/REUTERS

North Korea’s oppressive regime has caused numerous defections over the years and it appears there are five more this week. The New York Times reported that South Korea found a boat Saturday with four North Korean men and one woman sailing across the ocean border between the two countries.

The North Koreans were picked up by the South Korean Coast Guard off the eastern coast of the country and had indicated they wanted to defect.

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“Investigators from relevant government agencies are currently interrogating them to determine whether the North Koreans want to defect and other details,” said Choi Su-jun, an officer at the Coast Guard to the New York Times.

The boat was discovered after 7 p.m. and brought to the port of Mukho.

According to the New York Times, seven North Korean boats have traveled into South Korean waters this year, carting 28 people. So far, 21 out of the 28 have decided to return home to the North, with two defecting and the five picked up Saturday still under investigation. Thousands of North Koreans have fled the country, over 30,000 to South Korea since 1998 according to the South Korean Unification Ministry. Many more have defected to China and other countries.

In June, two soldiers defected from North Korea one on June 13 and one on June 23, according to Nikkei Asian Review (NAR) Sunday.

Defecting across the Chinese border is much easier and can happen for a bribe of between 40,000 to 50,000 yuan or $5,880 to $7,350, NAR reports. Crossing across the South Korean border is harder due to the large amount of military built up on the North Korean side of the demilitarized zone (DMZ). The DMZ is a 160-mile long, 2.5-mile wide strip that separates the two Koreas. The zone was established in 1953 after the Korean War, it runs adjacent to the 38th parallel.

Both soldiers were malnourished NAR reported.

The apparent defections come at a tense time for North Korea, as the U.S. has ratcheted up its rhetoric against the country.

President Donald Trump tweeted on Friday about a policy shift from his predecessor, Barack Obama.

“The era of strategic patience with the North Korea regime has failed,” wrote Trump.

North Korea has had 10 missile tests this year in its quest for a nuclear weapon able to reach the U.S. Tensions were further ratcheted up by the death of American student Otto Warmbier. The 22-year-old student who spent 17 months in a North Korean president after allegedly stealing a propaganda poster while he was there as a tourist. He was returned to his native Ohio in June in a coma and with severe brain damage, and he subsequently died.

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The Trump administration has leaned on their Chinese counterparts to put more pressure on North Korea, though China has resisted taking an overly aggressive tack with its southern neighbor. The U.S. announced economic sanctions Thursday on Chinese businesses and indviduals with ties to North Korea.

South Korean President Moon Jae-in met with Trump this week to discuss North Korea and other Issues. Moon, a liberal, has taken a softer stance towards Pyongyang.