The death toll from Monday’s suicide bombing attack of a mosque in northwestern Pakistan has risen to at least 100 people.

More than 150 others were wounded in the bombing in central Peshawar, the capital city of Khyber Pakhtunkhwa province. Rescuers were still pulling victims out of the rubble Tuesday. The explosion was so powerful that the roof of the building collapsed.

The victims were mostly members of the provincial police force, as the mosque was frequented by security and government officials. The attack occurred during traditional afternoon prayers.

Police officials would not immediately discuss the nature of the attack, saying an investigation was underway.

Prime Minister Shahbaz Sharif “has condemned the suicide mosque bombing” in Peshawar, an official statement said in Islamabad, the Pakistani capital.

Former Prime Minister Imran Khan, leader of the main opposition in Pakistan, also denounced the bombing, calling it a “terrorist suicide attack” in a Twitter post.

“It is imperative we improve our intelligence gathering & properly equip our police forces to combat the growing threat of terrorism,” Khan said.

U.N. Secretary-General Antonio Guterres condemned the blast as “abhorrent” Monday through his spokesman.

No one has taken responsibility for the deadly bombing.

The Pakistani province borders Afghanistan and has experienced repeated terrorist attacks in recent months. Most of the violence in the past is claimed by the outlawed Tehrik-i-Taliban Pakistan, known as the Pakistani Taliban.

The Pakistani Taliban, in a statement released to media outlets, including VOA, said it did not carry out Monday’s deadly attack.

Some information in this report came from The Associated Press, Reuters and Agence France-Presse. Richard Green contributed to this report.