An anti-tamper system including: a fixing device and an anti-tamper detection device; the fixing device comprising a body and a head whereby the head having a larger cross section then the body for enabling a tool to engage and drive the body into a first material layer thereby makes a firm connection with the anti-tamper detection device between the head and the first material layer; the fixing device further comprising a lock wherein the head is locked to the body by the lock where there is no external magnetic field and wherein the head becomes disengaged from the body when the lock is unlocked by an external magnetic field; and whereby the anti-tamper detection device detects and records a change the connection when the head becomes disengaged.