Islamic police in Nigeria’s Kano state have told shopping malls and local media to stop using the term Black Friday “with immediate effect”, suggesting it’s derogatory to Muslims who regard Friday as a holy day.

“Note that the Hisbah Corps will be around for surveillance purposes with a view to avoiding occurrence of any immoral activities as well as maintaining peace, harmony and stability in the state,” read one such letter sent to radio station Cool FM.

It’s not clear whether those who do not comply will be penalised following the controversial move.

Kano is one of several Muslim-majority states in northern Nigeria that practices Sharia law.

Their Islamic Police Board, known as Hisbah, said it was taking action following a petition by complainants who oppose its use, though the board did not reveal their identities.

The Islamic police have also warned against physical contact between men and women as people rush to buy low-priced goods during the occasion, saying officers would be on patrol to ensure compliance.