Noteworthy were the privately financed but Army-operated anti-aircraft guns, positioned on suspected approach routes that would overfly the industries that put up the money for them.[1] The Dutch Army Cavalry, which had no operational tanks, deployed several squadrons of armored cars, mainly near the strategical airfields. The German follow-up attacks overland were three-pronged (Frisia-Kornwerderzand, Gelderland-Grebbe Line, Brabant-Moerdijk) and were all stopped either fully or long enough to allow the Dutch army to demolish the German airmobile divisions and mop up the lightly armed paratroopers and airborne troops around The Hague. This circumstance, together with the anti-aircraft guns, of which German intelligence had not been aware because they had been purchased by civilians, contributed to the failure of the German crack units of paratroopers and airborne infantry to capture the Dutch government and force a quick surrender.