The incident in Morocco's commercial capital, Casablanca, is the latest in a spate of collapses at aging mosques, including one in February in which 41 worshippers were killed.

The three injured were taken to hospital for treatment and one was later discharged, Morocco's official MAP news agency said.

Officials have said dozens of mosques and minarets in Morocco are in dangerous condition because they are often centuries old and in need of repair.

Morocco's Islamic Affairs minister told Reuters in an interview earlier this year the government would double spending on a rebuilding program

, but he warned there could be more collapses before the work was complete.