Four people have been arrested on suspicion of facilitating a suicide bombing that killed more than 30 people on Friday, Pakistan's interior minister has said. Mohsin Naqvi said an Afghan national who is alleged to be the mastermind behind the attack was among those detained. One counter-terrorism officer was killed and three more were wounded in the raids to arrest the suspects. The Islamic State group has claimed responsibility for the bombing that targeted Friday prayers at the Shia mosque in the Tarlai area when it was packed with worshippers.

More than 160 people were injured in the blast, which was the deadliest in the capital for more than a decade. Huge crowds were seen in the city on Saturday, as thousands of mourners gathered for the funerals of the bombing's 32 victims. Funeral prayers took place amid tightened security, with soldiers standing guard and police checkpoints set up in key areas.

Ashiq Hussain, who lost his 21-year-old nephew Mujtaba Ali in the attack, told the Reuters news agency his family was broken. Condemning the attack on Friday, Pakistan's Prime Minister Shehbaz Sharif expressed deep grief. The country's President, Asif Ali Zardari, said targeting innocent civilians is a crime against humanity.

Eyewitnesses and survivors of the blast have shared harrowing accounts of the chaos following the explosion, with reports of bodies lying everywhere. Announcing the arrests on Saturday, Naqvi accused India of funding those behind the attack and providing them targets. In response, the Indian foreign ministry condemned the bombing and rejected accusations of involvement as baseless.

Pakistani Defence Minister Khawaja Asif suggested Afghanistan may have been involved in the attack. The Afghan Taliban government described his comments as regrettable, alleging that he made claims without credible evidence. Naqvi has pledged to enhance security in Islamabad, including recruiting thousands of new police officers and improving the city's smart security systems.

The violence in Islamabad follows a week of brutality in Pakistan, where coordinated attacks in Balochistan resulted in the deaths of 58 civilians. The Balochistan Liberation Army (BLA) has claimed responsibility for those attacks. As security continues to be a concern across the region, Pakistanis are left mourning the loss of innocent lives while calls for justice and better security measures grow louder.