Six Pakistani security personnel were killed and 16 injured on Tuesday when militants attacked a check post in the country's restive Khyber tribal region.
Militants attacked a check post in Shalobar area in Khyber Agency.
State-run Radio Pakistan quoted officials as saying that six security personnel were killed and 16 others injured.
Security forces retaliated against the attack and forced the militants to retreat, the officials said.
TV news channels reported that militants attacked four check posts in Shalobar area.
The reports said personnel of the Frontier Corps and Khasadar militia were among those killed in the overnight clash.
The militants attacked the troops with heavy weapons that damaged one of the check posts.
The attacks occurred in an area dominated by the Lashkar-e-Islam group led by warlord Mangal Bagh Afridi.Pakistan sacks Baluchistan government
Key Taliban commander among five killed in Pak blast
Video: Series of blasts in Pakistan kill 122
Two more killed in fresh attacks on polio workers in Pak
Abducted Sikh beheaded by terrorists in Pak tribal belt