The only offshore mosque in Azerbaijan, on the man-made town called Oily Rocks, has been razed, RFE/RL's Azerbaijani Service reports.
State oil company SOCAR says the reason for the demolition is due to preparations for Oily Rocks' 60th anniversary, in which structures without a certain architectural style are being demolished.
SOCAR spokesman Nizameddin Quliyev said the mosque was also built on a weak foundation.
But some religious NGOs say there are political reasons for the mosque's destruction, namely a fear that Islam is strengthening in Azerbaijan.
Haci Shahin Hasanli, imam of Baku's Mashadi-Dadash Mosque, said "some officials are trying to take Azerbaijan back to Soviet times, and regard religion as a danger."
A mosque in the Yasamal district of Baku was pulled down last month. A Turkish mosque in central Baku was closed for restoration purposes earlier this month, and last year the Abu Bekr Mosque was closed for security reasons.