After surfacing and picking up survivors, who were accommodated on the foredeck, "U-156" headed on the surface under Red Cross banners to rendezvous with Vichy French ships and transfer the survivors. En route, the U-boat was spotted by a B-24 Liberator bomber of the US Army Air Forces. The aircrew, having reported the U-boat's location, intentions and the presence of survivors, were then ordered to attack the sub. The B-24 killed dozens of "Laconia"s survivors with bombs and strafing attacks, forcing "U-156" to cast into the sea the remaining survivors that she had rescued, and to crash dive to avoid being destroyed.