At 18.04 hours on 22 Jun, 1940, U-65 reported the sinking of an unescorted tanker of 7000 tons with a spread of two G7e torpedoes in the Bay of Biscay. The ship was immediately covered in burning oil and apparently broke in two before it sank.
On 17 June, the Monique had been re-routed to Brest and then to Belle-Ile due to the German advances, but was reported missing after being last seen by the French motor tanker Rhéa in the evening on 17 June. The only trace found was the body of one of her sailors, washed ashore later near La Coruña, Spain. A radio message indicated that the ship had been attacked by aircraft off Verdon on 21 June, but it is more likely that she was sunk by this U-boat attack one day later.