Hostage 1
When you come to the part in the chapter where you are first taught about AR mode, you'll see four enemies below. Two will be in the street with the hostage and the other two will be one level up. Go to the left side, down the stairs and jump across the broken bridge. Get behind the first enemy and wait. There's an enemy on the enclosed bridge to the left. Wait for him to turn his back and kill this first guard before getting closer to the bridge. Wait for him to turn away again before kill him. With these two enemies down, circle the rest of the way around and come up behind the two enemies on the road. Kill them both from behind without being seen. Talk to the hostage to "rescue" him.
Hostage 2
There will be a mini-boss fight with a Hammerhead Chopper. Following this, you'll find yourself back in the streets. There will be several enemies blocking the street and they'll have the Hostage amongst them. To save this hostage, you will need an EM grenade to stun the enemies first.
