At least 128 people were killed after a suicide bomber targeted an election rally in Pakistan’s Balochistan on Friday, Reuters reported quoting unidentified officials. The Islamic State claimed responsibility for the attack. Balochistan Awami party candidate Siraj Raisani was among those who died in the Mastung blast.

The attack followed another suicide bombing that killed four people earlier that day.

The attacks occurred amid tensions over former Prime Minister Nawaz Sharif’s return to the country and his and his daughter Maryam Nawaz’s arrest in Lahore on Friday.

Pakistan is scheduled to go to the polls on July 25.

The province had been a target of militant groups Taliban, al Qaeda and Islamic state along with ethnic Baluch fighters who have been fighting the Central government.