(Compass) – Two years after seven Christians were gunned down at the Karachi headquarters of a Christian welfare agency, local police investigators have failed to identify a single suspect. Tomorrow marks the second anniversary of the execution-style massacre of seven staff members shot to death on September 25, 2002, in their downtown office of the Institute of Peace and Justice (IPJ). Of the two Christians who survived the attack, 26-year-old Robin Sharif remains partially paralyzed due to a gunshot wound to the head. The other, Robin Piranditta, has been in hiding and separated from his family since his release from police custody. The IPJs long-time watchman was subjected to severe torture for 27 days while undergoing interrogation in connection with the shooting. Three separate sources who have carefully studied the case told Compass that mounting evidence indicates that members of Pakistan s secret police were directly involved in the IPJ murders.