Security guards who work at Citycon Shopping Centres, the Talvivaara mine, the industrial park in Harjavalta and several district courts were among those taking part in the labour action.

The workers say they are dissatisfied with personnel policies, the position of chief shop stewards and safety at work.

The guards belong to the security professional union Turvallisuusalan ammattiliitto which is a member of the Service Union United PAM.

Jukka Myllymäki, the service director at ISS Palvelut, gave no comment when asked how security would be ensured if security guards walk off the job.