The robbers were caught on CCTV, __ their guns into the ceiling of the bank. shot were shot shooting were shooting

1. The robbers were caught on CCTV, **shot** their guns into the ceiling of the bank.<br /><br />2. The robbers were caught on CCTV, **were shot** their guns into the ceiling of the bank.<br /><br />3. The robbers were caught on CCTV, **were shooting** their guns into the ceiling of the bank.<br /><br />4. The robbers were caught on CCTV, **shooting** their guns into the ceiling of the bank.<br /><br />The correct answer is option 1: "shot". This is because it correctly describes an action that happened in the past and is consistent with the past tense used in the sentence.