In a significant development, security forces have unearthed a 130-metre-long and six-foot-deep tunnel constructed by Maoists in Chhattisgarh’s Bijapur on Tuesday. The well-concealed tunnel with an opening of four to five feet was discovered by the members of a police patrolling party from neighbouring Dantewada in Tadopot — a Bijapur village along the district’s border with Dantewada — around 11 …