Pakistan's military killed at least 14 militants in air strikes and a ground operation in a restive tribal region near the Afghan border on Tuesday.

The army offensive took place in the mountainous terrain of Rajgal in Khyber region, one of the seven semi-autonomous tribal districts where the military has been fighting Taliban and Al-Qaeda linked militants for over a decade.

"The operation was conducted in areas close to Afghan border in which 11 terrorists were also injured," the military said in a statement.

Pakistan has been battling a homegrown Islamist insurgency since 2004, following the US-led invasion of neighbouring Afghanistan in 2001 and the subsequent spillover of militants into its territory.

The army launched the "Zarb-e-Azb" operation in June 2014 in a bid to wipe out militant bases in North Waziristan tribal area and so bring an end to the bloody insurgency that has cost thousands of civilian lives.

Security in the country has since improve. Scattered attacks still take place, but they are fewer and of a lesser intensity than in previous years.