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In the folder were the general circumstances of Broson's investigation into the bank robbery these past few days.
In six bank robberies, except for the third bank which had a hidden camera installed in a fire sprinkler, in all other banks, their cameras were sprayed out with black paint by the robbers the moment they entered.
Therefore, this hidden camera that recorded the entire process of the bank robbery became an important guide for Broson's operations.
Based on the video records of the camera, Broson deduced that the two bank robbers were a group of ex-military personnel, or had military experience, hence, the entire operation was executed very skillfully and decisively.
During subsequent inquiries at the scene of the second robbery, when questioning bystanders and bank staff trapped inside the bank, Broson's team received another piece of information: one of the robbers had a tattoo resembling a snake pattern on his right wrist.