called the Mannerheim Line was located on the Karelian Isthmus approximately from the Soviet border. The Red Army soldiers on the Isthmus numbered 250,000, facing 130,000 Finns. The Finnish command deployed a defence in depth of about 21,000 men in the area in front of the Mannerheim Line to delay and damage the Red Army before it reached the line. In combat, the most severe cause of confusion among Finnish soldiers was Soviet tanks. The Finns had few anti-tank weapons and insufficient training in modern anti-tank tactics. According to Trotter, the favoured Soviet armoured tactic was a simple frontal charge, the weaknesses of which could be exploited. The Finns learned that at close range, tanks could be dealt with in many ways; for example, logs and crowbars jammed into the bogie wheels would often immobilise a tank. Soon, Finns fielded a better ad hoc weapon, the Molotov cocktail, a glass bottle filled with flammable liquids and with a simple hand-lit fuse. Molotov cocktails were eventually mass-produced by the Finnish Alko alcoholic-beverage corporation and bundled with matches with which to light them. 80 Soviet tanks were destroyed in the border zone engagements. By 6 December, all of the Finnish covering forces had withdrawn to the Mannerheim Line. The Red Army began its first major attack against the Line in Taipalethe area between the shore of Lake Ladoga, the Taipale river and the Suvanto waterway. Along the Suvanto sector, the Finns had a slight advantage of elevation and dry ground to dig into. The Finnish artillery had scouted the area and made fire plans in advance, anticipating a Soviet assault. The Battle of Taipale began with a forty-hour Soviet artillery preparation. After the barrage, Soviet infantry attacked across open ground but was repulsed with heavy casualties. From 6 to 12 December, the Red Army continued to try to engage using only a single division. Next, the Red Army strengthened its artillery and deployed tanks and the 150th Rifle Division forward to the Taipale front. On 14 December, the bolstered Soviet forces launched a new attack but were pushed back again. A third Soviet division entered the fight but performed poorly and panicked under shell fire. The assaults continued without success, and the Red Army suffered heavy losses. One typical Soviet attack during the battle lasted just an hour but left 1,000 dead and 27 tanks strewn on the ice. North of Lake