A ranking North Korean military officer in charge of conducting intelligence operations defected to South Korea last year, Seoul's Defense Ministry said Monday. 
A North Korean senior colonel, whose name has been withheld, defected in 2015 after working at the North's reconnaissance bureau tasked with carrying out espionage missions against the South, the ministry said. 
A source familiar with North Korean affairs said that the officer is viewed as an elite among North Koreans who have defected to the South, according to (Yonhap) news agency. 
"He is believed to have stated details about the bureau's operations against South Korea to authorities here," the source said. 
Kim Yong-chol, a new party secretary handling inter-Korean affairs, had served as the head of the bureau since 2009. 
In a separate case, a North Korean diplomat stationed in an African country and his family members defected to South Korea in May last year, said another source with knowledge about North Korea.

Source: QNA