Islamabad, Pakistan (CNN) -- Two children looking for valuable scraps in a garbage pile were killed Monday when a bomb targeting security forces went off in southwest Pakistan, police said.
The children were about 12 years old, officials said.
The bomb was planted near a gas station in Quetta and exploded moments after a military vehicle drove by, said police official Faridullah Bareech.
Police said none of the security personnel was injured, but three civilians were.
Quetta is the capital of the Balochistan, a province rich in natural resources near the Afghan border that is battling an insurgency.
Militants there have for years complained that the central government has paid little attention to them and their economic needs.
They have been fighting Pakistani military forces for self-rule. Pakistan has said the militants in Balochistan do not have links to the Islamic hard-liners who have launched assaults in other parts of the country.