Prime Minister Imran Khan in a message on the fourth anniversary of the terrorist attack on Peshawar's Army Public School reiterated the nation's resolve towards national, regional and world peace, Radio Pakistan reported on Sunday.

The prime minister said that the massacre had united the whole nation against a common enemy, which he described as a "blot on humanity".

He added that education is the best tool to eliminate extremism and terrorism permanently.

Read more: 144 stories: Remembering lives lost in the Peshawar school attack

Prime Minister Khan paid tribute to members of the armed forces and law enforcement agencies who have rendered countless sacrifices in the war against terror.

The premier expressed the government's commitment to turn Pakistan into a society which does not tolerate extremism or violence in the name of sect, religion, language, skin colour or ethnicity.

The prime minister also tweeted about his government's commitment towards the implementation of the National Action Plan (NAP), saying:

"Today as we remember and pray for the survivors and the victims' families, especially the parents, of the Peshawar APS terrorist attack. My government commits itself to fully implementing NAP to rid Pakistan of all forms of terrorism, violence & hatred."

President Arif Alvi said that the APS incident is a national tragedy as well as a day to re-pledge our commitments against inimical forces.

He urged the nation to be ready to make every sacrifice to curb extremism in the country.

Foreign Minister Shah Mehmood Qureshi said the fateful day of the APS attack continues to remain a scar on the collective memory of the nation. "Even after four years, the pain and sorrow of this utterly senselessness and heinous act remains fresh."

A memorial was also arranged at APS Peshawar today to pay homage to the martyred students and teachers of the school. Similar events were also held in other parts of the country.

Chief of Army Staff (COAS) Gen Qamar Javed Bajwa also shared a message via the Inter-Services Public Relations' Twitter account: "Remembering and praying for our APS Martyrs. Salute to the brave parents. Nation has bravely faced challenges at heavy cost to come out successful. We stay united and steadfast to carry forward Pakistan to its rightful destination of peace and prosperity, IA.”

Deadliest attack

In the deadliest terror attack in the country’s history, at least 144 people ─ mostly schoolchildren ─ were killed when heavily armed militants stormed the army-run public school on Dec 16, 2014. Seven soldiers of the Special Services Group and two officers were among the wounded.

When the nightmare unfolded, teachers and students had just returned to their classes after recess. Some students were gathered in the large auditorium and were attentively listening to a lecture.

Days after the attack, the government launched the National Action Plan (NAP) to counter terrorism in January 2015.

NAP comprised policy initiatives aimed at wiping out terrorist outfits across the country, integrating security efforts of the federal and provincial governments by engaging all the stakeholders, dismantling terrorist networks and ensuring deterrence by utilising available capabilities and resources of security organisations to overcome internal threats to state security.

Read more: An amended or new NAP?

The newly elected government plans to unveil a new version of NAP and restructure the National Counter Terrorism Authority (Nacta) to effectively tackle internal threats to security.

Coined NAP-2, the plan is aimed at bridging the gaps in the first version rolled out in January 2015. According to a document, the interior ministry plans to create a cyber security organisation to effectively counter the growing threat of cybercrimes.

The interior ministry plan also envisages restructuring Nacta to make it more functional, building capacity of civil armed forces, upgrading the safe city project and taking steps to curb currency smuggling from airports and borders.