North Korea has appointed a new vice marshal, Hyon Yong-chol, the official KCNA news agency says.
This comes a day after the army chief, Ri Yong-ho, was removed from his post "due to illness".
The decision was made by the Central Military Commission of the Workers' Party of Korea and the National Defense Commission of North Korea, KCNA said.
The statement did not say if Mr Hyon was taking over the top military job from Mr Ri.
Little is know of Mr Hyon, who is reported to be a member of the party's 120-member central committee.
He is believed to have been appointed a general in 2010 but is not currently part of the military commission chaired by young leader Kim Jong-un, reports said.
Ri Yong-ho's removal took many North Korea observers by surprise, with widespread scepticism at the official explanation for the move.
He was seen as a key figure in the recent transition of power in the communist state from Kim Jong-il, who died in December 2011, to his son, Kim Jong-un.
A spokesman for South Korea's Unification Ministry told reporters that Mr Ri's departure was "very unusual".
Some analysts say ''illness'' is not an uncommon pretext in Pyongyang when a member of the elite leadership is removed.
Mr Ri was also vice-chairman of the powerful Central Military Commission and held top posts in the ruling Workers' Party.
He was made army chief three years ago under Kim Jong-il and appeared regularly at state occasions.