The Yemeni Government has reported that a hoard of Axumite (Ethiopian) and late Roman gold coins previously in the inventory of the Aden Museum were stolen during the ongoing civil war.

The coins are further described in a publication entitled, STUART MUNRO-HAY, The al-Madhāriba Hoard of Gold Aksumite and Late Roman Coins, The Numismatic Chronicle (1966-) Vol. 149 (1989), pp. 83-100 (available at https://www.jstor.org/stable/42667572?seq=1#page_scan_tab_contents).

Furthermore, the Antiquities Coalition, an archaeological advocacy group, is also publicizing this loss.  See https://theantiquitiescoalition.org/uncategorized/publics-help-needed-to-recover-blood-antiquities/  (see linked publication at pages 117-144).

You should contact national law enforcement authorities if you are offered  any of these coins.