SB 4.10.8

sa tān āpatato vīra
 ugra-dhanvā mahā-rathaḥ
ekaikaṁ yugapat sarvān
 ahan bāṇais tribhis tribhiḥ
Synonyms: 
saḥ — Dhruva Mahārāja; tān — all of them; āpatataḥ — falling upon him; vīraḥ — hero; ugra-dhanvā — powerful bowman; mahā-rathaḥ — who could fight with many chariots; eka-ekam — one after another; yugapat — simultaneously; sarvān — all of them; ahan — killed; bāṇaiḥ — by arrows; tribhiḥ tribhiḥ — by threes.
Translation: 
Dhruva Mahārāja, who was a great charioteer and certainly a great bowman also, immediately began to kill them by simultaneously discharging arrows three at a time.