Abstract: A security paper is provided that includes at least one layer of fibrous substrate and a security deposit thereon. The at least one layer has a main body of a substantially uniform thickness and at least one aperture and/or zone of reduced thickness. The reduced thickness is non-zero and at least 15% less than the thickness of the main body. The security deposit includes at least one element that partially covers the fibrous substrate exposed in the at least one aperture and/or zone of reduced thickness. Therefore, when the at least one layer is split through its thickness into first and second portions, a hole is provided in the first portion and the at least one element is provided on the fibrous substrate of the second portion. A method of manufacturing the security paper and security documents including the security paper are also provided.