Two children were killed when security forces and suspected pro-Taliban militants traded fire in North Waziristan, officials said on Tuesday.The battle in Banda village took place on Monday after militants fired 11 rockets at a military checkpost and troops retaliated with artillery, a security official said. Some shells hit a few houses and two children, aged five and 11, were killed. Six people, two children and four women, were wounded, the official added. Separately, three soldiers were injured when militants fired rockets on checkposts, the military said in a statement. It said the three were injured when militants fired mortar rounds and rockets on two separate checkposts.