Parliamentary Secretary Julia Farrugia has called in the police after somebody wrote under a video of the Auberge de Castille on her Twitter account that this was a good place for bombing testing.
Ms Farrugia's tweet marked Pride Week and showed Maltese and Gay Pride rainbow flags outside the Office of the Prime Minister.
Ms Farrugia is responsible for administrative reforms and citizenship.
Earlier on Wednesday a man was held under arrest after being arraigned and accused of making threats against the police in a Facebook post about the use of speed guns.