At least 25 people were killed in fighting between two rival militant groups in Pakistan's restive north-western region along the Afghan border, a security official said on Saturday. According to dpa, the fighting in the remote Tirah valley in Khyber tribal district between Lashkar-e-Islam and militant groups started on Friday evening and continued through Saturday morning. "We believes that around 25 people have been killed in the fighting," a security official said on condition of anonymity. He said most of fatalities were militants from the rival groups.