If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
USA intelligence spotted an illegal trading business on the dock. the army have sent you to the location to stop them. You have to eliminate all of them and stay alive to complete this mission. but beware, the dirty armies are so dangerous and are great in numbers.
Mouse - Aim / Shoot.
1-2 - Weapons.
Spacebar - Reload.