The Sierra Leonean Deputy High Commissioner to Nigeria, Nelson Williams, was kidnapped in Kaduna State on Friday.
A retired Nigerian Army General confirmed the incident to SaharaReporters.
According to the source, the kidnappers are asking for millions of naira as ransom before freeing the envoy.
The diplomat was on his way to attend a function at the Armed Forces Command and Staff College in the State, the source added.
While the location of the abduction in Kaduna State has not been confirmed, one source said it happened between Abuja and a a bordering local government area in Kaduna state.
At the time of publication, there has been no official briefing by the Kaduna State Police Command, Department of State Services, or the military.