Police are investigating the assault of a Free State referee, whose jaw was fractured in two places by a player during a game, the Volksblad reported on Thursday.

E.J. King was assaulted in the final minutes of the second league club game between Police and the Defence Force at Bobbies Park in Bloemfontein on Tuesday.

The Free State Rugby Union said in a statement King was assaulted by a player from the Police club in the scoring area just before the final whistle.

His jaw was broken in two places and he lost two teeth.

"The Free State Rugby Union sees the incident in a serious light. This is absolutely unacceptable," the statement read.

The union said disciplinary steps would be taken against the culprit after the matter was investigated and a hearing had taken place.

Police spokesman Lieutenant-Colonel Annelie Wrench confirmed the incident and said a charge of assault with intent to do grievous body harm had been laid.

Spokeswoman for the Life-Rosepark hospital, Esmarie Cronjé, said King's condition was satisfactory after surgery on Wednesday.

SAPA