CHARSADDA, Dec 23: Two Afghan refugees are among four suspects picked up for questioning in connection with the Charsadda mosque suicide attack on Eid day which left at least 56 people dead and over a hundred others injured.

Security officials said the men, one of them a madressah student as well as a local prayer leader, were held in addition to two others detained earlier.

Civilian and military investigators are hunting for clues in the suicide bombing, which targeted former interior minister Aftab Ahmed Khan Sherpao.

The suicide bomber struck while Eidul Azha prayers were being offered in the mosque inside Mr Sherpao’s residential compound.

The former minister and his elder son Sikander Sherpao, who were the bomber’s main target, escaped unhurt.

Forty-one people were killed on the spot and another 15 died later in hospitals in Peshawar and Charsadda.

“Suicide attackers don’t believe in any religion. They mindlessly kill innocent people for reasons unknown to us,” remarked Ghazi Khan, who had lost two brothers in the explosion.

This was the second attempt on the life of Mr Sherpao. In April this year, he narrowly escaped a suicide bombing in Station Koroona in his home district of Charsadda. Twenty people were killed in that incident.

Charsadda District Police Officer Feroz Shah told Dawn that police had taken stringent security measures for Eid prayers at another place inside the compound, but the venue was changed at the eleventh hour in line with Mr Sherpao’s instructions.

One intelligence source said the bomber was in the eighth row of worshippers while Mr Sherpao himself was in the front row.

He said the explosion had caused craters in the ground near the eight row.

Hours after the blast which left the mosque strewn with human limbs and pieces of clothing and shoes, police and intelligence agencies sleuths picked up four suspects from a seminary in the nearby Tarangzai village.

Two of the suspects hail from Afghanistan’s southern Helmand province, a stronghold of Taliban insurgents and the so-called drug capital of the war-ravaged country, an intelligence official said.

He said the second attempt on Mr Sherpao’s life appeared to have been carried out by the same group which had organised the first attack.

The group behind the first attack, he said, was based in the neighbouring Mohmand tribal region.

The injured included Sherpao’s son Mustafa Sherpao and nephew Dil Araam Khan. Mustafa, Mr Sherpao’s younger son, had received pellets in his leg and his condition was stated to be stable, Sikandar Sherpao said.

Officials said the former interior minister had been warned of possible suicide attacks by insurgents.

Provincial Police Chief Muhammad Sharif Virk said there had been no headway in the investigations and they were looking for clues to identify the group involved in the bombing.

“It’s still too early to say whether any headway has been made,” Mr Virk told Dawn. He said the bomber carried explosives weighing between 8 and 10 kilograms.

Meanwhile, an investigation team led by Additional Inspector-General Fayyaz Turu has been constituted. It includes Mardan DIG Ghulam Muhammad and Superintendent Police (Investigation) Kashif Alam.