Bus drivers from the La Louvière depot walked out on Tuesday after a colleague was robbed at gunpoint.
The strikes come a week after rail workers launched wildcat action after two colleagues were assaulted. Workers voted 29 to 24 in favour of strike action, agreeing that there would be no blockades or impediments to non-strikers.
In spite of this only one bus ran on Tuesday and workers voted to continue strike action. There have also been reports of dsolidarity action at other depots.
Management has offered some concessions to workers, as well as cctv cameras for certain routes.