Pakistani forces killed 27 suspected militants in air strikes and a ground operation Thursday in the restive northwest hours after a roadside bomb killed three soldiers, officials said.

The government and military have reaffirmed their determination to defeat the Taliban following the school massacre in the northwestern city of Peshawar on Tuesday.

Air strikes Thursday killed 17 militants in troubled Khyber tribal district, where the Taliban and other Islamist fighters have taken refuge.

"Seventeen terrorists were killed in effective air strikes this evening. Killed terrorists include one of the top Uzbek terrorist commanders Islam ud Din," the military said in a statement.

In an earlier ground action in Bajaur, another tribal area on the Afghan border, security forces killed 10 militants.

"In a ground action by security forces at Malak Shaga Nullah near Warwandu Mella and Hossai Nullah 10 terrorists were killed, two were seriously injured while 6-8 managed to escape," a senior security official told AFP.

He said two security personnel were wounded and others were chasing the fleeing militants.

The operation came hours after a roadside bomb killed three paramilitary soldiers in Bajaur, around 200 kilometres (125 miles) northwest of Peshawar.

"Three paramilitary soldiers were killed when they walked over an IED (impoverished explosive device) planted on a roadside in Damadola area of Bajaur tribal district," local official Suhail Khan told AFP.

He said the troops were returning to their camp after a routine patrol when they stumbled over the device.

Abdul Haseeb Khan, another senior official, confirmed the incident.

Nobody immediately claimed responsibility for the attack but the Pakistani Taliban, and its splinter factions, have regularly targeted security forces in the northwest.

On Tuesday, a team of Taliban gunmen stormed the Army Public School in Peshawar, slaughtering 148 people, including 132 children, in the country's deadliest ever terror attack.

The Pakistani Taliban said the assault was revenge for the killing of its fighters and their families in an ongoing military operation against its hideouts in the North Waziristan tribal area, and warned more attacks would follow.

Pakistan has been battling Islamist groups in its semi-autonomous tribal belt since 2004, after its army entered the region to search for Al-Qaeda fighters who had fled across the border following the US-led invasion of Afghanistan.