Pakistani officials say a roadside bomb has killed six militants in the country's northwest.
Officials say a militant commander named Hakim Khan was among those killed in Thursday's attack in the Kurram tribal region near the Afghan border.
It was unclear who planted the bomb, but officials say a rival militant group may be responsible.
In southern Pakistan, the port city of Karachi began to return to normal on Thursday following days of political violence that killed at least 56 people.
Schools and businesses reopened in Pakistan's commercial hub following a day of mourning.
The killings began Saturday, ahead of Sunday's by-election to replace provincial lawmaker Raza Haider from the Muttahida Quami Movement, who was gunned down in Karachi in August.
Rival political parties blame each other for the violence.
Some information for this report was provided by AP and Reuters.