City University staff union members staged a protest rally yesterday in the escalation of a row with management over freedom of speech. The demonstration by around 100 City University of Hong Kong Staff Association members and students was sparked by campus security guards taking photographs of posters hung in union members' offices. The posters are part of a campaign that started last week accusing the management of suppressing free speech by taking over the staff association's office, claiming it was 'required for other purposes'. Last Saturday, staff members saw security guards taking photographs in offices with posters supporting union activities, including the name plates on the office doors. 'If you are going to take pictures, do it out in the open. Don't take the pictures on a Saturday when no one is there,' said Professor John Tse Wing-ling, chairman of the staff association. CityU announced on Tuesday that it would stop all photographing activities by the security guards, but the union is demanding that the pictures be erased, and the sacking of management staff who ordered that the photographs be taken. 'It is already despicable of them to suppress the union, but even more despicable to suppress freedom of speech,' Tse said. The staff association has disseminated video footage of the security guards' photo-taking activities for public viewing. CityU said yesterday that the photo-taking 'has been a longstanding, routine practice of the security guards' as a 'building management measure and has nothing to do with freedom of expression'. The university stressed it did not infringe on free speech because 'no one has been asked to remove the posters', and it had not obstructed the staff association from announcing the rally freely and openly through campus e-mails and posters.