Some of the six South Koreans sent home from North Korea on Friday had entered the hardline communist state in search of a better life, a report said on Sunday.

The six were taken into custody for questioning after being handed over — along with the body of a woman — at the border truce village of Panmunjom.

One of the six was the woman’s husband, identified only as Lee, who had strangled her in an aborted suicide pact, the South’s Yonhap news agency quoted authorities as saying.

It said they went to North Korea illegally between 2009 and 2012 — either by jumping off a Chinese cruise ship in rivers along the North Korea-China border, or by walking across the rivers when they were frozen.

They said some of the men, whose ages ranged from 27 to 67, had posted pro-North Korea comments on the Internet under false names.

They “had fallen under the delusion that they would be treated well by the North Korean government when the communist country’s official media introduced them by their pseudonyms”, Yonhap said.

Some of them had only managed to find work in the South as day labourers due to family troubles or other hardships, and decided to defect, hoping for a better life in North, it said. While more than 23,500 North Koreans have escaped to the South from the North since the end of the Korean War in 1953, defections the other way are very rare.

The men said they had been held and questioned in various detention centres across North Korea for up to 45 months and also expressed a sense of betrayal at the way they had been treated .Formal arrest warrants have been sought for the six before further questioning.

They could be charged with violating the strict National Security Law, which bans unauthorised contacts with the North, while Lee could also be charged with murder, authorities added.