The Professional Achievement
Complete the street chase in Comrades in under 2 minutes 30 seconds without dying
In the mission "Comrades" when you chase down the nuke carrier, the chase starts from when you run into the police crossfire. Quickly advance up the side of the street, taking out the police reinforcements ASAP. The chase ends when the nuke carrier fires the RPG out of the tunnel, and your achievement will unlock if you completed in time.