On 7 March 1941, U-70 attacked convoy OB-293 southeast of Iceland, but was lost after a second attack at 07.25 hours. The survivors claimed that they had hit three ships in the first attack at 04.45 hours and another in the second. In fact they had hit Athelbeach and Delilian in station #71 and #61 during the first attack and Mijdrecht during the second.

The Mijdrecht (Master J. Swart) was approaching a lifeboat from Delilian when she was hit by one torpedo on the starboard side, about six feet forward of the engine room bulkhead. The master spotted the periscope of U-70 on the starboard bow, rammed the submerged U-boat at a speed of 7 knots and reported its position to the escorts. The tanker managed to reach Rothesay Bay on 19 March, was temporary repaired at Govan and later went to Middlesbrough for permanent repairs.

The conning tower of U-70 had been badly damaged, but the pressure hull remained intact and Matz decided to head away from convoy for repairs. At 08.15 hours, HMS Camellia (K 31) (LtCdr A.E. Willmot, RNR) sighted the U-boat on the surface, which dived shortly afterwards. Until 10.30 hours, this corvette and HMS Arbutus (K 86) (LtCdr H. Lloyd-Williams, RNVR) carried out five attacks with depth charges, followed by another four attacks by HMS Arbutus (K 86) alone. Altogether the corvettes dropped 48 depth charges in the nine attacks. The U-boat was forced to surface after the last attack at 12.44 hours and had to be abandoned by the crew. 25 survivors were picked up and taken prisoner by the corvettes.