Two separate militant attacks left at least 12 people dead, including children, in Pakistan's troubled Khyber tribal district on Saturday, officials said.
Some 18,000 people last month fled their homes in Khyber, near the Afghan border, amid fears of a fresh onslaught of fighting between the army and Islamist militants tied to the Pakistani Taliban.
"At least six people including two children and a woman were killed when a mortar fired by militants fell on a house in Tirah valley," a senior local administration official, Saeed Ahmad Jan, told AFP.
He said that the militants apparently wanted to target a nearby checkpost of security forces but missed.
And in Bara town a group of 20-25 militants from the Lashkar-e-Islam (LI) group attacked a checkpost of the paramilitary Frontier Corps, triggering a gunfight.
"The exchange of fire left six militants dead and 10 others wounded," Jan said, adding that troops arrested all the injured rebels.
Pakistan's army has previously launched a series of offensives targeting the LI, a Taliban-allied militant group waging a local insurgency.
Pakistan's seven tribal districts on the Afghan border are rife with a homegrown insurgency and are strongholds of Taliban and Al-Qaeda operatives.
Pakistan has launched operations along parts of the lawless belt but has withstood US pressure to wage battle with the Haqqani network, which is blamed for some of the worst attacks in Afghanistan.