A Toronto father and son who were arrested while in the "advanced stages" of planning a violent attack have been charged with multiple terrorism-related offences, the RMCP say.

Ahmad Fouad Mostafa Eldidi, 62, and Mostafa Eldidi, 26, face a total of nine charges; including conspiracy to commit murder for the benefit or at the direction of a terrorist group — namely the Islamic State, a Sunni Muslim militant group.