(KUNA) -- One armed assailant was killed and three more people were arrested during a coalition forces' operation in southern Afghanistan, a statement by the US forces said on Thursday.The operation was conducted in Tirinkot, capital of the country's southern Uruzgan province, in search of a Taliban commander "responsible for conducting anti-government activities." During the search, the coalition forces came under fire from the compound. In an exchange of fire, one of the assailants was killed while three more people were detained from the site. "Coalition forces remain focused on defeating insurgent networks in Afghanistan," said Capt Vanessa R. Bowman, spokesperson for the US-led coalition troops.