Cross Fire

Official Site

Cross Fire is an online military first-person shooter for the PC, developed by SmileGate and Neowiz, and co-published by G4BOX and Wicked Interactive. Players assume the role of either a Black List or Global Risk mercenary, and then join an online team that must work together to complete objective-based scenarios. Cross Fire's flagship feature is its "Ghost Mode", which puts one team in possession of top-secret cloaking technology, rendering them invisible to the opposing team. This team of "ghosts" is armed only with knives, and must stealthily track and hunt the enemy team. This mode is exclusive to Cross Fire and no other mode exists quite like it in any other first-person shooter.

Here a video description

Look's like counter-strike