TORONTO - Residents of south-central Ontario they may see or hear low-flying aircraft on Thursday and Friday.

NORAD says it's conducting exercises this week in the region in preparation for next month's G8 summit in Huntsville, Ont., and the G20 summit in Toronto.

The exercise will involve Canadian Forces CF-18 Hornet fighter jets and Sea King and Griffon helicopters flying at low altitudes.

NORAD says residents in the exercise area may hear aircraft noise and perhaps see aircraft flying at various times throughout the day.

NORAD says it will not discuss specific details of the exercises "to maintain the integrity of its air defence mission."

The G8 summit June 25-26 in Huntsville will be immediately followed by a larger meeting of the G20 leaders in Toronto on June 26-27.