its founder and leader mohammad yousuf was killed while in police custody. from then on the crew became increasingly violent. no it's not entirely clear what its fighting for what is clear is that it's become a powerful fighting force. some experts say it's better equipped to manage your your army. it's estimated that iran has killed several thousand people. report to police officers and soldiers are frightened and right away rather than protect the civilian population. they have reason to be scared there are plenty of videos of vocal from korea the captured soldiers . other. this morning we headed west to grouchy the journalist whose research the history of the group . muhammad has reported on vocals around for years. he shows us the spot where it launched its first major attack four years ago does it. it was good then a policeman stops us saying we are conditioned to fill the right. this is all set or what. tips. the top of the sceptical about its history. for dinner. i support them. cheese the spencer trust to the police station. this incident highlights