Image copyright AFP Image caption The attack on the Peshawar school left 150 people dead

A militant who masterminded a deadly attack on a Pakistani school in 2014 has been killed in a US-led air strike, US and Pakistani officials say.

Umar Naray allegedly planned the attack on an army public school in Peshawar that left 150 people dead - mostly children and female teachers.

He led a group linked to the Pakistani Taliban, US defence officials said.

He was killed over the weekend in Nangarhar province, in Afghanistan near the border with Pakistan, they added.

Naray "orchestrated multiple terrorist operations in Pakistan to include the January 2016 attack on Bacha Khan University, the September 2015 Badaber Air Force Base attack, and the December 2014 Peshawar school attack that resulted in the deaths of more than 130 children," US defence department spokesman Peter Cook said.

Image caption The Pakistani Taliban released a photo showing Naray (centre, in blue) and other armed militants following an attack

Naray led the Tariq Gidar Group, which was a militant faction with ties to the Pakistani Taliban, Mr Cook said.

He was killed "along with four other enemy combatants in a US forces-Afghanistan air strike" targeting a faction of the Islamic State group, he added.

Naray was also known by several other names including Khalifa Umar Mansoor and Khalid Khurasani.

Stepped up offensive

The US had informed Pakistani army chief Gen Raheel Sharif of the death, a Pakistani army spokesman said.

There was no official comment from the Pakistani Taliban. However, one commander confirmed the death to Reuters, calling it "a huge loss to the small but most effective Taliban faction".

The December 2014 Peshawar school attack, where militants went from classroom to classroom shooting at students and teachers, sent shockwaves through Pakistan.

Following the attack, Pakistan lifted a seven-year moratorium on executions, while the army stepped up its military offensive against militants in the border regions.