Compulsory military service
Section 220(1) · 1999 Constitution (2004 edition)
What Constitution says
(1) The Federation shall establish and maintain adequate facilities for carrying into effect any Act of the National Assembly providing for compulsory military training or military service for citizens of Nigeria.
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 98. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections