However, by this time Brigadier General Charles Drake's supply corps, although desperately attempting to move tons of food, ammunition, fuel, and medical supplies to the Bataan Peninsula, were hampered by air raids, lack of vehicles, lack of personnel, and, most importantly, lack of time, even with General Jonathan Wainwright's Northern Corps fighting a delayed retreat.[67] As a result, they were only able to relocate a portion of the much needed supplies to the peninsula. In addition, the pre-invasion construction of the planned Bataan fortified defensive positions had also been neglected.