Operation Rimau was an attack on Japanese shipping in Singapore Harbour, carried out by an Allied commando unit Z Special Unit, during World War II using Australian built MKIII folboats. It was a follow-up to the successful Operation Jaywick, which had taken place in 1943, and Rimau, a shortened version of the word Harimau (which is Malay for tiger). It was again led by Lieutenant Colonel Ivan Lyon of the Gordon Highlanders. Originally named Operation Hornbill the aim of Rimau was to sink Japanese shipping by paddling the folboats in the dark and placing limpet mines on ships. It was originally intended that motorised semi-submersible canoes, known as Sleeping Beauties, would be used to gain access to the harbour, however, they resorted to folboats. Thirteen men, including Lyon, were killed.