sentences:  This deterioration was due to the British Army's heavy-handed treatment of Catholics and nationalists in their efforts to combat republican paramilitaries.For example, on 5–7 July 1970, up to 3,000 troops sealed off the lower Falls area and conducted an aggressive search for arms - an episode known as the Falls Curfew.Five civilians were killed and over 60 injured in gun battles between the troops and the Official IRA (who at that time were the dominant IRA faction in that part of Belfast).