A commuter train exploded this afternoon in Taiwan, injuring 21.
Police suspect that a small pipe bomb, around 15-20 centimeters (6-8 inches) long, hidden in a black backpack, caused the explosion.
"It looks like someone did it on purpose," Premier Lin Chuan told journalists. "We will make our best efforts to investigate this case. Please rest assured that we will provide effective and efficient security for all passengers."