"U-570" quickly resurfaced and around 10 of the crew emerged. The Hudson fired on them with machine guns, but ceased when the U-boat crew displayed a white sheet. The captured crew members later recounted to British naval intelligence interrogators what had happened—the depth charge explosions had almost rolled the boat over, knocked out all electrical power, smashed instruments, caused water leaks, and contaminated the air on the boat. The inexperienced crew believed the contamination to be chlorine, caused by acid from leaking battery cells mixing with sea-water, and the engine-compartment crew panicked and fled forward to escape the gas. Restoring electrical power—for the underwater electric motors and for lighting—would have been straightforward, yet there was nobody remaining in the engine compartment to do this. The submarine was dead in the water and in darkness. Rahmlow believed the chlorine would make it fatal to stay submerged so he resurfaced. The sea was too rough for the crew to man their anti-aircraft gun so they displayed a white flag to forestall another, probably fatal, depth charge attack from the Hudson—they were unaware the aircraft had dropped all its depth charges.