Images of two Quebec City police officers equipped with a fire extinguisher as they escorted a prisoner suspected of setting fire to his ex-wife were raising eyebrows on Sunday, with some observers criticizing the move as a tasteless joke.

However the union representing both officers, the Fraternité des policiers et policieres de la Ville de Quebec, defended the decision, saying in a communiqué that the fire extinguisher was a "preventive security measure" during the escort of the prisoner.

Union president Marc Richard expressed his dismay over the suggestion the officers were behaving in an unprofessional manner.

The prisoner, Frej Haj-Messaoud, 39, was arrested in Drummondville on Saturday by the Sureté du Québec and charged with attempted murder and aggravated assault in connection with an attack on Friday that left his 27-year-old ex-wife with burns on over half her body.

He is expected to return to court in Quebec City on Monday.