A suicide bomber has killed at least 20 people, believed to be militants of the Lashkar-e-Islam group, in north-west Pakistan.
The Taliban said the suicide bombing was a revenge attack. There have been sporadic clashes between the groups.
The blast in Khyber tribal agency came hours after 10 soldiers and at least 22 Lashkar-e-Islam militants were killed in clashes in the same area.
The military and several militant groups are fighting to control Khyber.
None of the reports can be independently confirmed as there is no media access to the area.
Reports indicated that the suicide bomber detonated his explosives jacket in the presence of a large number of Lashkar-e-Islam fighters.
A spokesman for the local Taliban said the blast was to avenge the killing of their fighters at the hands of the Lashkar-e-Islam gunmen two months ago.