The white helmets are the Syrian civil defence. They are trying to rescue as many people as possible after the catastrophic and inhumane attacks on the civil population done, among others, by the regime of Assad.
The White helmets are now fighting since 2013 against attacks by bombs and IDE, especially the infamous barrel bombs.
The BBC reported that between January 2014 and May 2015, only 1% of the victims of barrel bombs were rebel fighters [Link].
This is war crime and the responsible persons should be called to account for.
Checkout their movie - "The white helmets" - Hopefully available soon as DVD.
Those guys are Badass. I bow my head in appreciation for your duty.