The United States and Iraq said ISIS blew up a historic mosque in Mosul that was the ideological heart of the terror group and the birthplace of its self-declared caliphate.
Iraq Prime Minister Haider al-Abadi said the ISIS act amounts to "an official announcement of their defeat." His military commanders said militants blew the mosque up after troops closed in.
(However, this is contested by ISIS.) Whether or not this report is accurate, this leads me to question:
Question: Is it forbidden to destroy a mosque during times of battle?
It sounds like it should be forbidden. I'm aware of numerous things that the Prophet (ﷺ) forbade during times of battle; here's just one example:
It is narrated by Ibn 'Umar that a woman was found killed in one of these battles; so the Messenger of Allah (ﷺ) forbade the killing of women and children. -- Sahih Muslim 1744