A written account states that in 1361, the Grand Master of the Teutonic Knights Winrich von Kniprode issued an order to gather information about the castle, specifically the thickness of its walls, as preparation for an assault on the castle. In March–April 1362, the castle was besieged by the Teutonic Order. During this attack, the Teutonic Knights constructed a siege tower and erected wall-penetration machinery; primitive fire arms might have been used, since gunpowder technology was emerging in Europe. At that time, the castle walls were over high, when its firing galleries are factored in. According to Wigand of Marburg, the castle's garrison consisted of about 400 Lithuanians soldiers, commanded by Vaidotas, son of Duke Kęstutis. After three weeks, the Knights managed to breach the castle's walls, and soon afterwards the castle was taken. On Easter Sunday in 1362, the knights conducted a Mass at the castle to commemorate their victory.