Last night an explosion on a commuter train carriage in Taipei Songshan railway station wounded at least 21 people. The Criminal Investigation Bureau conducted an investigation on the crime scene and found the explosives.
Some witness on that train said that a man in black, about 40 years old, carrying a big black bag, may be the suspect who did this. The Police examined the CCTV camera images very carefully but nothing found so far. The Home Land Security agent also participated in the investigation on this suspicious terrorist attack.
As a forensic guy, I suggest them focusing on the wounded victims. The reason is that the bomb was not Detonated by remote control, so the suspect may hide among those victims. Filtering out suspicious persons and seize their phones, laptops/ PCs, find out what's related to this attack. Let the evidence speak for itself.