New Delhi, June 11 -- The Delhi government's Anti-Corruption Branch (ACB) on Tuesday issued fresh summons to senior Aam Aadmi Party (AAP) leader and former deputy CM Manish Sisodia in connection with alleged irregularities in the construction of classrooms in government schools. He has been asked to appear before investigators on June 20, officials familiar with the matter said. The summons were issued after Sisodia failed to appear for questioning on Monday, citing prior commitments. ACB is probing violations in a project to construct 12,748 semi-permanent classrooms, initially valued at Rs.860 crore. The cost of the project reportedly rose to over Rs.2,800 crore without fresh tenders or adherence to standard procurement procedures. The project in question was executed during Sisodia's tenure as Delhi's education minister, officials said....