Choke Point by Brad Thor
This is another in the exciting Scot Horvath series. It starts with a huge explosion in Bangkok. Scott and his team are sent to find the bomber and call on CIA agent Morrell and local cop Davi for help before he strikes again. Then there is a second explosion--and they hear word of a possible third one, which makes the task even more stressful. The action keeps cutting between Scott, the bomber, and a former Marine suffering from PTSD who may be onto what is really going on in Thailand, putting his life in danger. Once you can keep track of all the characters, it's a gripping thriller.