A man, 41 was arrested in Qormi late yesterday after assaulting a police constable.
The incident, in Victory Street, happened when the man caused a disturbance and the off duty policeman intervened and was assaulted.
The man, who was wielding a knife, took the pepper spray cannister from the officer and tried to use it on other people before running off, with the officer in pursuit.
The man was arrested after other officers arrived. Both the man and the officer were slightly injured.