At least four people were killed and 32 injured in a bomb blast that was targeted at the convoy of former Chief Minister Akram Khan Durrani on Friday in Khyber Pakhtunkhwa province.

The ex-CM, who was returning from an election rally near North Waziristan, was unaffected by the remote controlled blast in Bannu city, Dawn online quoted a senior police official as saying.

The injured were taken to District Headquarter (DHQ) Hospital in Bannu for treatment.

Caretaker Chief Minister Dost Mohammad Khan condemned the incident and summoned an emergency meeting to discuss the security situation.

Durrani is contesting the July 25 general election on NA-35 (Bannu) against Pakistan Tehreek-i-Insaf (PTI) Chairman Imran Khan on Muttahida Majlis-i-Amal (MMA) ticket.

This is the third major attack in the province during election campaigning, Dawn reported.

On Monday, Awami National Party (ANP) candidate from Peshawar Haroon Bilour and 19 others were killed in a suicide blast.

The Tehreek-i-Taliban Pakistan (TTP) owned up the blast. It had also claimed responsibility for a 2012 attack that killed Haroon's father, Bashir Bilour.

Earlier this month, an attack on PTI candidate's office in North Waziristan's Razmak tehsil had injured 10.