Leftist SYRIZA's radical Group of 53 faction has condemned the use of "unjustifiable violence" by riot police officers, referring to clashes with demonstrators protesting property foreclosures in Athens on Wednesday.
In a statement, the group questioned "whether there is the political will to curb and ultimately wipe out phenomena of suppression."
The group underlined the need for a "democratization" of the Greek Police (ELAS), calling for a ban on the use of tear gas by officers.
Four police officers and five demonstrators were injured in the fracas outside a notary's office in Athens on Wednesday.
Three leftist activists have been indicted to trial on a string of charges including resisting arrest, disturbing the peace and causing grievous bodily harm to a police officer.