while another 34 intruder patrols were flown. 32 Halifax and three Stirlings took part of "Gardening" operations off the French coast and Frisian Islands. 40 aircraft flew supplies to the French Resistance also. Greiner was scrambled to intercept the stream heading to Saint Ghislain. At 00:15 south of Brussels Greiner claimed a Halifax. Flying west, Greiner attacked another northwest of Oudenaarde at 00:30. The last of the two inflated his tally to 25. On 9 May, and successive nights over the 12–13 May, and again on 25 May, Greiner claimed single victories against two Halifax and two Lancaster bombers. Greiner claimed his last victories of the month on 27/28 May. Bomber Command committed 331 heavy bombers against Leopoldsburg. At 02:29 and 02:48, Greiner claimed two Lancaster bombers, to bring his total to 31 bombers destroyed. The location of the engagements are recorded as Antwerp. The last was probably a Lancaster of No. 640 Squadron RAF piloted by Flying Officer F. Williams DFM, who was killed with two other crewmembers. The month of May was Greiner's most successful of the war. On 1 June 1944 Greiner was promoted to Hauptmann. Five days later, Operation Overlord began with the Allied invasion of Normandy. 11./NJG 1, stayed in Sint-Truiden but extended its area of operations deep into France. Bomber Command sent out 225 Lancaster and 86 Halifax bombers to France supported by 18 Mosquitos on 15/16 June 1944. The No. 1, 3, 4 and 8 Groups attacked railway targets at Evreux, Gare de Massy – Palaiseau, Nantes and Tours. Near Paris at 01:26, Greiner claimed a Halifax for victory 32. On 15/16 June 1944, 227 aircraft (119 Lancaster, 99 Halifax and nine 9 Mosquito) from 4, 5 and 8 Groups attacked an ammunition dumps at Thorigné-Fouillard and a fuel dump at Châtellerault. The 5 Group raid at Châtellerault destroyed 8 fuel sites out of 35 in the target area without loss. 224 aircraft (184 Lancaster, 30 Stirling, 10 Mosquito bombers) of 3 and 8 Groups attacked railway yards at Lens and Valenciennes. Six Lancasters were lost from the Lens raid and five Lancasters from Valenciennes attack. 31 Mosquitos bombed to Gelsenkirchen, and 34 intruder patrols were carried out. Another seven Stirling and four Halifax bombers flew "Gardening" sorties minelaying off Channel ports. One Mosquito was lost from the Gelsenkirchen raid. Greiner attacked a Lancaster from an unknown bomber stream northeast of Lille at