A complex security checkpoint, comprising: a first block detecting a threat 1, which is explosives or Improvised Explosive Device; a second block detecting a threat 2 which is metal weapons; a third block detecting a threat 3 which is radioactive and/or nuclear material; a processing unit receiving data from all blocks and determining a presence of any threat; wherein data from the first block is used in determining explosives or Improvised Explosive Device and metal weapons, the data from the second block is used to determine metal weapons and wherein the third block includes a spectroscopic device for detecting radioactive and/or nuclear material, which provides an energy spectra of gamma-ray sources detected, thus allowing to eliminate naturally occurring radioactive materials and reduce false alarm; an alarm which is starting in case of a threat presence; wherein the alarm indicating a type of the threat: explosives or Improvised Explosive Device, metal weapons or radioactive and/or nuclear material; and wherein the explosives are plastic explosives hidden under a garment; and the first block performs measurement of a phase delay and an amplitude of a microwave MW radiation; the checkpoint further comprising transmitters irradiating the radiation reflected by the garment and a human body or passed through the garment; and the second block receives the MW radiation using a first polarization receiver; the polarization receiver includes a first polarizer which passes through only MW radiation with polarization turned 90 degrees compared to an initial polarization of the radiation irradiated by the transmitters. a first block detecting a threat 1, which is explosives or Improvised Explosive Device; a second block detecting a threat 2 which is metal weapons; a third block detecting a threat 3 which is radioactive and/or nuclear material; a processing unit receiving data from all blocks and determining a presence of any threat; wherein data from the first block is used in determining explosives or Improvised Explosive Device and metal weapons, the data from the second block is used to determine metal weapons and wherein the third block includes a spectroscopic device for detecting radioactive and/or nuclear material, which provides an energy spectra of gamma-ray sources detected, thus allowing to eliminate naturally occurring radioactive materials and reduce false alarm; an alarm which is starting in case of a threat presence; wherein the alarm indicating a type of the threat: explosives or Improvised Explosive Device, metal weapons or radioactive and/or nuclear material; and wherein the explosives are plastic explosives hidden under a garment; and the first block performs measurement of a phase delay and an amplitude of a microwave MW radiation; the checkpoint further comprising transmitters irradiating the radiation reflected by the garment and a human body or passed through the garment; and the second block receives the MW radiation using a first polarization receiver; the polarization receiver includes a first polarizer which passes through only MW radiation with polarization turned 90 degrees compared to an initial polarization of the radiation irradiated by the transmitters.