A security cap (1) for selectively closing an open end (3) of a pipe (5). The security cap (1) includes inner and outer cap assemblies (7, 11), at least one latch (17), and a driving assembly (21). The outer cap assembly (11) is rotatable with respect to the inner cap assembly (7), and along with it, is intended to cover the open end (3) of the pipe (5). Each latch (17) is cooperable with the inner and outer cap assemblies (7, 11), and displacable with respect to the cap assemblies (7,11) so as to be operated between first and second configurations, wherein in the first configuration, each latch (17) is drawn away from an outer groove (19) of the open end (3) of the pipe (5) thereby enabling the security cap (1) to be removed from the open end (3) of the pipe (5), and wherein in the second configuration, each latch (17) is engaged with the outer groove (19) thereby preventing the security cap (1) from being removed from the open end (3) of the pipe (5). The driving assembly (21) is operatively disposed between the inner and outer cap assemblies (7, 11), and cooperable with the same, as well as with the at least one latch (17), for selectively driving each latch (17) between the first and second configurations via a given rotation of the outer cap assembly (11) with respect to the inner cap assembly (7) of the security cap (1).