The death toll from a suicide bombing at a wedding near the Afghan border rose to seven on Saturday, police said, as Pakistan struggles to deal with a rising wave of militant attacks.

The bombing tore through a building housing members of a peace committee during a wedding ceremony on Friday in northwestern Pakistan's Dera Ismail Khan district, said police official Muhammad Adnan.

The committees are made up of local residents and elders and supported by Islamabad as part of its efforts to counter Islamist militants in the regions along the Afghan border.

The four, who were among nearly a dozen people hurt in the attack, died in hospital, Adnan added.

Three people were confirmed dead on Friday.

No group has claimed responsibility for the bombing.

The Pakistani Taliban, also known as Tehreek-e-Taliban Pakistan, which operates on both sides of the Afghan border, has labelled peace committee members as traitors.

The Pakistani Taliban is an umbrella group of several Sunni militant groups, which has been fighting against the state since 1997.

Their stated goal is to replace Pakistan's system of governance with their strict brand of Islamic laws.

Islamabad has accused the Afghan Taliban of allowing the Pakistan group to plan its attacks from Afghanistan. Kabul denies the charge, saying the militancy is Pakistan's domestic problem.