This is during mission 8. At the beginning you have to chase Faraz down.
I would recommend playing on easy and not rushing. Don't shoot when Faraz is on the screen if you can avoid it, and avoid dying (I'm unsure if checkpoints will count)
Faraz will take you on a really crappy route through his compound when a number of enemies pop up and try to shoot at you, none of them should be difficult by this point in the game, just keep pressing forward, and following him. I believe I captured him in under 10 minutes on easy after a few failed attempts (trying to run past gun fights).
If you are having trouble on Medium or Hard, I'd recommend trying it on easy.