The 44-year-old general secretary of Athens’s association of cleaners and domestic staff was in a coma yesterday after being attacked outside her home in the district of Petralona early on Wednesday by assailants who threw acid into her face.

Constantina Kouneva, who is Bulgarian, has lost her sight in one eye and has been unconscious since the attack, which police believe may have been an act of revenge for her trade union activities for which Kouneva has reportedly received death threats. It is thought that the hit might have been planned by members of gangs seeking to control firms offering cleaning services.

A group of around 80 demonstrators staged a rally outside Athens’s Evangelismos hospital late yesterday to express solidarity with Kouneva, who is in the intensive-care unit there. The rally was mostly peaceful but a police patrol car passing in front of the hospital was pelted with stones by a group of youths. The stones broke the car’s windscreen but caused no injuries.