During all parts of the war, use of chemical and biological weapons were extremely limited by both sides. Italy used mustard gas and phosgene during the short Second Italo-Abyssinian War, Germany employed chemical agents such as Zyklon B against Jews, political prisoners and other victims in extermination camps during the Holocaust, and Japan employed chemical and biological weapons in China. In 1943 a U.S. ship carrying a secret Chemical Warfare Service cargo of mustard gas as a precautionary retaliatory measure was sunk in an air raid in Italy, causing 83 deaths and about 600 hospitalized military victims plus a larger number of civilian casualties. In the event, neither chemical nor biological weapons were used on the battlefield by any combatant during World War II.