They are the most feared gunmen in Syria.
They have the blood of thousands on their hands. Both sides in the war deploy them.
And in the city of Homs they are all busy.
These are the snipers of a long and deadlocked war.
They work on top floors and tall buildings. They sit often in near darkness and total silence. They are always ready to shoot; they kill for a living.
We were allowed to peek into their murky, lethal world in Syria's deadliest city.
To get to them we had to go deep into a devastated district, debris and bullet casings everywhere, every house pockmarked with the holes of a long war. We dashed across road junctions where rebel snipers pick off the troops who run too slowly.
The speed at which the soldiers sprint across different streets shows you which junctions are the deadliest.
Then, towards the frontline, even the streets are too dangerous and we clamber through holes in houses and walls, up staircases and into the gloom where the snipers sit.
The four we saw were young men with hard faces. Their enemy is as close as fifty yards away.
Even though we were there with our camera, they hardly took their eyes off the target - in one case, it was a balcony where the sniper was waiting for a rebel gunman he'd spotted earlier to reappear.
I felt almost queasy watching it; hoping the man would stay hidden.
Theirs is a war of single shots. Outside though, machine guns fired in a fierce and almost incessant battle.
And theirs is a war of fixed positions.
Since May, the frontline has moved no more than five hundred yards.
One hundred yards a month, at a cost of hundreds of lives. A day ago, five Syrian soldiers were killed here.
So the snipers watch and wait; time on their hands, lives in their hands.
I once spent time with British army snipers in Iraq. I vividly remember how they worked. Slow down your heartbeat, control your breathing.
When you see your target, breath out and lightly draw the trigger back to fire. It was almost gentle.
With a deadly end. Oddly, what they wanted most was what they called a clean kill. Instant death. Two shots were a failure.
I thought of them as I watched the young Syrian men, waiting in the darkness, finger lightly on the trigger, muzzle through the crack in the wall, death on their minds, victory in their sights.