Approach the gate with caution. As soon as you climb the steps leading up to the gate, a cut scene begins. The gate closes trapping you in the dead-end street, and a squad of about 8 Solarii converges from all directions.

You receive 100 XP for getting yourself trapped like a rat. To celebrate, immediately scramble for cover and start killing people. To the best of my knowledge, there's nowhere to run where you're safe from these guys, since they're coming in via your only escape routes: the street and the upper and lower levels of the building on the right. There are several piles of barrels, crates and tires you can hide behind. One has rifle/SMG ammo and shotgun shells behind it. Another has more rifle ammo and arrows.

Shoot from behind cover if you can.

There are a few conveniently placed red fuel barrels you can explode with bullets or arrows to kill or injure nearby foes.

If the gunfire gets too heavy, release Aim to duck down behind the pile of junk. When the enemies start throwing Molotov cocktails...

...scramble out of the way and take cover behind a different barrier. Use the rifle and/or fire arrows to take out as many enemies as possible as they approach.

If any get too close, switch to the shotgun. One blast at close range will take out most enemies.

Or, if you've unlocked the Dodge Counter skill, keep your weapon aimed as an enemy approaches. Then dodge back or to one side to trigger the dodge counter sequence.

Press Melee when the icon appears. In the screenshot above, the icon is about to appear. I wasn't able to hit the screencap button at the exact moment since I was a little distracted. ;)

You'll then see the Dodge Counter icon, shown above, as the enemy loses his balance, exposing his back. Move in closer...

...and press Melee again...

...to deliver a finishing attack.

Or just take him out with a shotgun blast. This works especially well on the guy with the metal shield.