sentences:  The offensive began at noon on 30 March 1972, when an intense artillery barrage rained down on the northernmost ARVN outposts just south of the DMZ.On 30 March the 258th Marine Brigade was deployed forward to Đông Hà.Early on the morning of 1 April under pressure from the PAVN the 4th Marine Battalion abandoned Firebase Sarge and retreated to Mai Loc Camp.