At around 04:15 the OoW on the bridge heard whistling and spotted a boat in the darkness coming close to H1 at 21kn speed. The boat had not appeared on the radar. It flashed a light, then left the scene, leaving 6 people in the water. At 04:30 we launched the RHIBs and were able to recover the 6 people. We then conducted a search pattern to ensure nobody else was left. We have them on board and now going to Bari, which is named as PoS by authorities.