At least four people were killed and over 20 injured in a suspected suicide blast in an election rally in northwest Pakistan on Friday, police and local media reported.

The bomber, who acted alone, rammed his explosive-laden motorbike into a vehicle minutes after the end of an election rally in the remote Bannu district, bordering the restless North Waziristan tribal region.

Senior politician Akram Kham Durrani, a candidate of the five-party religious alliance Muttehida Majlis Amal (MMA), was an apparent target of the attack but escaped unscathed, local broadcaster ARY News reported.

A former chief minister of the northwestern Khyber Pakhtunkhawa province, Durrani is running against Imran Khan, a popular former cricket star from Bannu.

Durrani told ARY News that he was not at the venue when the blast occurred.

This was the second attack on MMA candidates in Bannu in the last two weeks.

The bombing followed a suicide blast at an election rally earlier this week in Peshawar, Khyber Pakhtunkhawa’s capital, that killed 21 people, including a candidate.

The Pakistani Taliban's mother coalition, Tehrik-e-Taliban-Pakistan, had claimed responsibility for the Peshawar attack.

Pakistan’s elections are scheduled for July 25

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