KARACHI- Security has been deployed at historical sites of Pakistan, including the Mazar-e-Quaid in Karachi and tomb of Allama Iqbal in Lahore, due to a terror threat in the country today.Security was alerted and heavy contingents of law enforcing agencies deployed around the tomb of Quaid-e-Azam Muhammad Ali Jinnah. Initially entry of visitors was banned at Mazar-e-Quaid for three days but later people were allowed to visit the Mazar-e-Quaid after checking. However, they were not allowed to carry any shopping bag or other articles with them. The one side of M.A. Jinnah Road was closed for traffic as well. Heavy contingent of commandos, Rangers and other law enforcing agencies were deployed in the interior of the mausoleum. Meanwhile, security was tightened in key areas of Lahore which include Shrine of Data Darbar, Shahi Qila, Iqbal Park of Minar-e-Pakistan and the mausoleum of Allama Iqbal. In a letter to Punjab Government by Federal Interior Ministry, the provincial government was asked to increase patrolling in these areas by elite police force.