South Korea says North Korean leader Kim Jong Un had his military chief executed for corruption.

If true, the execution of Ri Yong Gil would be the latest in a series of killings, purges and dismissals since Kim took power in late 2011.

Details about North Korea's opaque government are notoriously difficult for outsiders to get, even national governments, and South Korean officials have a spotty record of tracking developments in North Korea.

A South Korean official said Monday that Ri's execution was part of Kim's effort to bolster his grip on power.

The official didn't say how the information was obtained and spoke on condition of anonymity because it involves confidential intelligence on North Korea.

The government had previously leaked the details to South Korean media.