Police arrested on Thursday afternoon a 33-year-old Belgian national for manufacture and possession of incendiary devices and for refusing to submit to fingerprinting.
The suspect, who was identified as an anarchist, was detained in the suburb of Papagou, in eastern Athens.
Officers found in his possession two improvised incendiary devices, six plastic containers with solid fuel, a container with flammable liquid, a manual gas burner and a pair of gloves.
The man was led before a prosecutor on Friday.
The case is being investigated by Attica's state security subdivision.