Last man standing - David Baldacci

Seven seconds. That's all it took for Web London to lose everything: his friends, his team, his reputation. Point man of the FBI's super-elite Hostage Rescue Team, Web roared into a blind alley towards a drug leader's lair, only to meet a high-tech, custom-designed ambush that killed everyone around him.
Coping with the blame-filled words of anguished widows and the suspicions of colleagues, Web tries to put his life back together. To do so, he must discover why he was the one man who lived through the ambush - and find the only other person who came out of the alley alive... a ten-year-old boy who has since disappeared. Acting on his instincts, Web believes he knows where the killer will strike next. Only this time, he may not survive the attack.
In his extraordinary new work, Baldacci uses his unsurpassed storytelling skills to explore the essence of survival itself, as a conspiracy of violence surrounds an FBI agent whose fate was to be the ... LAST MAN STANDING.