The narrator of this 1967 song sees his own tombstone. Somehow, on places such as Twitter, Procol Harum have been mixed up with Boko Haram.
Boko Haram is a Nigerian-based group, widely considered terrorist, that in 2014 abducted about 200 girls. It has done so as ransom for its own prisoners. It aims to establish a Muslim state based on sharia law. Its members and leadership oppose modern (Western) culture, and violently promote causes which may be ethnically motivated.