Portugal's public prosecutor has filed charges that could bring a prison sentence of more than 10 years against a policeman who beat a middle-aged football fan in front of his two young sons, with the video of the incident causing a national scandal.

The prosecutor's office says evidence suggests the policeman used excessive force in May 2015 when he punched Jose Magalhaes, then 42, twice in the face and hit him repeatedly with a truncheon outside the Guimaraes stadium in northern Portugal. Magalhaes was accompanied by his children aged nine and 13, with the youngest son screaming at officers to stop.

The prosecutor's office said on its website late Monday that the policeman is also accused of lying in his report of the incident to justify his conduct.