Pakistani security personnel inspect the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)

Damaged vehicles are seen at the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)

A Pakistani security personnel inspects a damaged vehicle at the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)

Pakistani security personnel inspect the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)

Pakistani security personnel inspect the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)

Pakistani security personnel inspect the blast site in southwest Pakistan's Quetta on March 29, 2014. A five-year-old girl was killed and 18 people were injured when a bomb went off near a vehicle of paramilitary troops in Pakistan's southwest Quetta city on Saturday afternoon, local media reported. (Xinhua/Asad)