ISIS appears to have claimed responsibility for the Tunisia museum massacre in an online audio recording posted on a website linked to the group, analysts told NBC News Thursday. The unsigned statement identified the two attackers that died in the siege and called them "knights of the Islamic State," according to security analysts Flashpoint Intelligence. No further details were immediately available about the unverified claim, and there was no immediate comment from Tunisian authorities. At least 23 people were killed in Wednesday's atrocity, including 20 foreign tourists.
