In an update to this post, several stories offer various bits of information that begin to create a more solid picture of the family’s motivations and the circumstances of their trip. Probably the relatives they left behind, if any, will be easily identities and may pay the price. From the Yomiuri Shimbun:

Four North Korean defectors submitted a statement to investigative authorities, written in Korean, criticizing the North Korean regime and outlining their reasons for wanting to flee to South Korea, it was learned Monday.

The married couple and their two sons, who fled the country by boat, criticized the system led by Kim Jong Il, saying: “We were dissatisfied and skeptical about the system [in North Korea], where incompetent leaders have turned society backward.”

From the Dong-a Ilbo:

The four took a small wooden boat lacking a cabin and even a cover and departed from Chongjin port at night on May 28 in search of freedom. Six days later, at 4:10 a.m. on June 2, they were spotted by a fisherman off the coast of Fukaura.

The four North Koreans said to the police, “We escaped from North Korea due to poor living conditions. We headed toward Japan since Korea maintains a heavy security presence on the border.”

[…]

The wooden boat they used is 7.3 meters long, 1.8 meters wide, and has two small engines.

Sausages, two sacks carrying drinks, several wooden oars, clothing, and a small bottle containing a liquid presumed to be poison were found on the boat.

The family said, “We planned to poison ourselves if we were captured by North Korean security forces.”

[…]

The Yomiuri Shimbun reported that the Japanese government will issue six-month valid temporary landing permission visas to the four once they are classified as defectors.

Via the AP:

Four North Korean defectors told Japanese authorities they were desperate to escape from extreme poverty and oppression in the isolated communist country, police and media reports said Monday.

[…]

The family told investigators they fled North Korea because “their life was so difficult that they could barely eat bread every other day,” prefectural police spokesman Shuetsu Toda said. Each submitted a statement requesting asylum in South Korea, he said.

When they arrived, they had only several sets of clothes, chopsticks, leftover sausage and rain gear on the boat, along with their identification cards, a small amount of North Korean money and other small items, Toda said. No weapons were found.

The four told police that they fled “to seek freedom,” and that there are “no human rights in North Korea,” the business newspaper Nikkei reported Monday.

They originally planned to go directly to South Korea after leaving North Korea’s northeastern port of Chongjin last Sunday on a 7.3-meter (24-foot) -long wooden, roofless boat. But they instead headed for the Japanese port city of Niigata to avoid tight security near the border between the two Koreas, Toda said.

[…]

The family said they had lived on a meager income from octopus fishing and had no acquaintance in Japan, Toda said. They headed for Niigata, linked by a ferry to North Korea until Tokyo imposed sanctions in October to protest the North’s atomic test, but ended up in Aomori due to the tide.

[…]

More than 130 people who have fled North Korea are currently in Japan.

From Kyodo:

The younger son in the four-person family of purported North Korean defectors who arrived in a boat in Aomori Prefecture was in possession of a minute amount of amphetamine, which is illegal in Japan, police sources said Monday.

But the police are unlikely to detain the octopus fisherman, who is in his 20s, as the government is stepping up diplomatic efforts to send the four to South Korea in line with the wish they have expressed in writing to the Japanese police, the sources said.