Pakistan Army and local tribes on Monday foiled an attempt of US troops to enter inside Pakistan's territory through two American helicopters. According to sources, US troops boarded on two helicopters were trying to enter onto Pakistan's areas near Angoor Adda along Pak-Afghan border when local tribes and troops of Pakistan army resisted the move and opened fire, forcing US helicopters to return. Sources said situation remains tense in the area while local tribals along with Pakistan army are also positioned to face any untoward situation.