Pakistani authorities have made several arrests in connection with the bomb attack at a mosque in the northwestern city of Peshawar that killed 100 people, police sources independently told news agencies.

Peshawar Police Chief Ijaz Khan told Reuters that several suspects had been arrested and police were investigating the possibility that they had received "internal assistance" to get inside the highly fortified compound where the mosque was located.

"We have found some excellent clues, and based on these clues we have made some major arrests," Khan told Reuters. "We can't rule out internal assistance but since the investigation is still in progress, I will not be able to share more details."

A senior official separately told AFP, on condition of anonymity, that police had detained 23 people in connection with the attack. The official also confirmed that they were investigating possible help from the inside, adding that they were looking into possible connections with groups outside of Pakistan.

What do we know about the attack?

On Monday, a suicide bomber blew himself up inside a mosque in a security compound in Peshawar during afternoon worship. More than 300 worshippers were in the building at the time.

It remained unclear how the attacker entered the high-security area, home to police and regional government headquarters, with explosives.

The head of the Khyber Pakhtunkhwa province police force, Moazzam Jah Ansari, had said on Tuesday that the attacker had entered the mosque as a guest before exploding 10 to 12 kilograms (about 22 to 26 pounds) of explosive material that had been brought into the compound beforehand.

No group has yet claimed responsibility for the attack. The Pakistani Taliban denied it had been involved after an initial assertion by one of its commanders.

The region — which runs along the border with Afghanistan — has seen a steady increase in violence since the Taliban took control of Pakistan's neighbor in August 2021.

Monday's attack was the deadliest in Peshawar since the 2013 suicide bombings of a Christian church.

Pakistan, which is facing numerous issues including violence, economic problems and the fallout of largescale flooding in 2022, is also preparing for elections later this year.

ab, tg/nm (Reuters, AFP)