Conlan argues that the "History of Yuan"'s account of the battle suggests that both the Japanese and Yuan forces were of similar size. Conlan estimates that both armies numbered around 3,000 each (not including the Yuan sailors) during this battle while Japanese historians estimate 6,000 defenders on the Japanese side. The Japanese forces, being inexperienced with non-Japanese tactics, found the Mongol army perplexing. The Yuan forces disembarked and advanced in a dense body protected by a screen of shields. They wielded their polearms in a tightly packed fashion with no space between them. As they advanced they also threw paper and iron casing bombs on occasion, frightening the Japanese horses and making them uncontrollable in battle. When the grandson of a Japanese commander shot an arrow to announce the beginning of battle, the Mongols burst out laughing.