As far as I know, no material evidence has been published. Certainly, I haven’t seen any, beyond quotes and paraphrases of an official statement by Iraq’s Ministry of Tourism and Antiquities. According to an anonymous antiquities official, ‘destruction began after noon prayers’. Nevertheless, if it hasn’t yet, as Abdulamir Hamdani observed, ‘it [is] just a matter of time’.
Apparently, the Islamic State ‘assaulted the historic [thirteenth-century B.C.E., Assyrian] city of [Kalhu/Calah/]Nimrud and bulldozed it with heavy vehicles‘, ‘heavy machinery’. To be precise, it began bulldozing the ancient city. Seemingly, the Islamic State also ‘used heavy military vehicles to transport the artefacts from Nimrud‘, though a more limited claim only asserts that ‘trucks that may have been used to haul away artefacts had also been spotted at the site’.
I’m away and offline for the next twenty-four hours at least.