 By the Han dynasty, crossbows were used as mobile field artillery and known as "Military Strong Carts".Around the 5th century AD, multiple bows were combined together to increase draw weight and length, thus creating the double and triple bow crossbows.Tang versions of this weapon are stated to have obtained a range of 1,160 yards, which is supported by Ata-Malik Juvayni on the use of similar weapons by the Mongols in 1256.