All the direct relatives, including children, of Jang Song Thaek, the late uncle of Kim Jong-un who was put to death on December 12 2013, have been executed in North Korea, according to South Korea’s Yonhap News Agency.

“Multiple sources” told Yonhap, a publicly funded news agency, that entire families related to Thaek have been executed.

Thaek was convicted of plotting to overthrow North Korean leader Kim Jong-un and the whole North Korean government, and was sentenced to death by firing squad at the end of last year. The North Korean regime issued photos of his arrest.

The execution of Thaek was announced by state TV, sending questions around the globe about what the risky and very public move might mean for the the current leader.

Kim Jong-un commented on his uncle’s death saying that the ruling party was stronger after being purged of “factional filth”.

In the days following Thaek’s execution there were rumors that his body had been fed to a pack of 120 dogs, although this story is now believed to have originated from a satirical post on a Chinese social network.

Among those allegedly executed from Thaek’s family are his brother-in-law and the country’s ambassador to Cuba Jon Yong-jin and Thaek’s nephew and ambassador to Malaysia Jang Yong-chol. The two diplomats were both recalled from their positions back to North Korea earlier this month.

Anonymous sources told Yonhap, which maintains close links to the South Korean government and its intelligence services, that the killings were a clear statement “that no traces of Thaek should be left.”

Website NKnews.org advised that Yonhap News Agency “has been wrong on North Korea news in the past, but was the first media organisation to report on the purge of Jang Song Thaek, days before it was announced by North Korean media”.