Islamabad:Most of the terrorists, who were involved in the brutal attack on an army school in the Pakistani city of Peshawar in December last year have either been killed or arrested, the Pakistani army said Thursday.

In one of the worst acts of human savagery ever perpetrated, the Pakistani Taliban slaughtered 150 people, 140 of them being children, in a brazen attack on the Army Public School in Peshawar Dec 16, in retaliation to the army operation against the extremists in North Waziristan.

Military spokesman Asim Bajwa said during a news conference that 27 terrorists were involved in the planning and execution of the attack, and nine of those have been killed in operations, according to a Xinhua report.

He said six terrorists involved in the attack were apprehended from Pakistan and six from Afghanistan, while others were still at large. The arrested men have also confessed to be involved in other terrorist attacks as well, Bajwa said.

He requested the Afghan authorities to hand over the accused to Pakistan in view of the growing security cooperation between the two countries.

\"We are thankful to the Afghan government for the arrests on (the basis of) our intelligence. I am hopeful that the Afghan government will extradite them,\" Bajwa said.

\"The school attack was planned on the Pakistan-Afghanistan border area,\" he said.

Bajwa said that Mulla Fazalullah, the chief of the Tehrik-e-Taliban Pakistan (TTP), the group behind the school attacks, and another terror mastermind, Umar Ameer were still in Afghanistan.

\"Both Pakistan and Afghanistan are constantly sharing intelligence and they will be arrested or eliminated soon,\" he said.

He said that the attack was carried out on the directions of Mulla Fazlullah, who chose Umar Ameer to supervise the attack. They had selected six suicide bombers for this purpose.

\"The terrorists first got all information about the school and (the) roads leading to its building,\" the army spokesman said.

Bajwa said that one of the facilitators also included a prayer leader in Peshawar who hosted three attackers for a night near the school.

On Dec 17, Pakistan ended its moratorium on death penalty in terror-related cases, following the Peshawar school attack and have executed a number of convicts so far.

Most Peshawar school attackers killed or arrested: Pakistan