KABUL, AFGHANISTAN — Militants in Pakistan fired rockets at NATO bases across the border in Afghanistan, killing three children in a village and prompting the alliance to launch a pair of retaliatory artillery strikes, officials said Sunday.
The clashes could heighten diplomatic tension over Pakistan's inability to stop Islamic militants from operating from its territory -- and whether forces in Afghanistan have the right to strike back.
North Atlantic Treaty Organization officials said five rockets were fired at one of their bases in Khowst province overnight. At least one rocket hit a house in Kunday, a small village between two military bases, killing the three children. Another hit one of the bases, injuring an Afghan man.
NATO said its forces responded "in self-defense" to the attack with artillery fire at the launch site in Pakistan.
In an earlier attack Saturday, three rounds of "indirect fire" -- which often refers to mortar or rocket attacks -- landed near a NATO outpost in Paktika province, the alliance said. Three more landed in an Afghan army compound. No casualties were reported.
NATO said those rounds also came from Pakistan and that it responded with artillery fire.
Pakistan, like Afghanistan, is a key ally of the United States in its campaign against international terrorism.
But Afghan and U.S. officials blame surging violence in Afghanistan in part on efforts by the new Pakistani government to make peace with Taliban militants on its side of the mountainous frontier.
Pakistan's army has pulled back some forces from its lawless tribal areas, where Al Qaeda and the Taliban find refuge, and has largely held fire during the truce talks.