MADINA: The Bureau of Investigation and Prosecution are investigating four drug traffickers who were found in possession of 3,000 Captagon pills which they had concealed in secret compartments in their car. They had driven all the way from the Northern Frontier to Madina to sell to students before the start of the examinations. Acting on a tip-off, the Anti-Drug Police in Madina deployed plain-clothed policemen at the checkpoints leading to Madina.