peshawar school aftermath
A Pakistani soldier shows members of the media a burnt-out classroom, the day after the attack by Taliban militants A Majeed/AFP

Pakistani police have issued a warning that Taliban terrorists are plotting to place magnetic bombs on buses carrying students to school.

Authorities based in Islamabad issued a letter which requested that schools increase their security measures and ensure that checks are made underneath buses transporting students and other vehicles.

The call comes after the Pakistani Taliban's massacre of 141 people - 132 of them children - at a military school in the city of Peshawar.

In response to the attack, Pakistani Prime Minister Nawaz Sharif reinstated the death penalty for those convicted of terrorism and called for three days of national mourning.

Government spokesman Mohiuddin Wan said: "It was decided that this moratorium should be lifted. The prime minister approved.

"Black warrants [execution orders] will be issued within a day or two."

In further action, the Pakistani army chief General Raheel Sharif and the head of the Inter-Services Intelligence agency (ISI) travelled to Afghanistan to meet newly-elected President Ashraf Ghani to talk about ways to tackle branches of the terror group in both countries.

"We are hoping that we will see strong action from the Afghan side in the coming days," said Pakistani army spokesman Major General Asim Saleem Bajwa.