District 187: Sin Streets is a first-person shooter video game developed by Netmarble, a subsidiary of CJ Corporation. An online multiplayer, the game pits SWAT teams and gangsters against each other in urban combat.
The game resembles Counter-Strike, including its "cops and robbers" setup, game modes and map layouts. It features an extensive weapon modification system that allows both mechanic and cosmetic upgrades. The game focuses on clans and team-based progression. Clans will compete for territory, with clan performance in four weekly "street fight" events determining possession of city districts.
District 187 is free-to-play, with all weapons available for in-game currency only. Players are charged real money for cosmetic modifications and for upgrades that speed up the acquisition of in-game currency.
Source: Wikipedia, "District 187: Sin Streets", available under the CC-BY-SA License.