A computerized method for suspicious message processing and incident response at a threat detection platform, comprising: electronically storing a defined textual or binary pattern associated with a security threat; receiving a suspicious message that was previously received at a messaging client, the message having been classified as suspicious by a user of the messaging client after receipt at the messaging client; electronically storing a pattern as a rule for determining whether a body of the received suspicious message or an attachment of the suspicious message contains a defined textual or binary pattern associated with a security threat; processing the received suspicious message according to the electronically stored rule to make a determination that the body of the received suspicious message or an attachment of the received suspicious message contains the defined textual or binary pattern associated with the security threat; and in response to the determination, associating the received suspicious message with a message group, the message group comprising of received suspicious messages having at least the defined textual or binary pattern in common, and each of the messages of the message group having been determined not to be a known simulated phishing attack based on an identifier or other message characteristic of the delivered message; and displaying a graphical representation of the message group in a user interface that enables an operator to perform batch operations on multiple of the suspicious messages in the group; and removing one or more messages from messaging accounts associated with multiple users based on a matching of at least a portion of header information of the delivered message or at least a portion of metadata of the delivered message with the one or more messages from the messaging accounts associated with the multiple users. electronically storing a defined textual or binary pattern associated with a security threat; receiving a suspicious message that was previously received at a messaging client, the message having been classified as suspicious by a user of the messaging client after receipt at the messaging client; electronically storing a pattern as a rule for determining whether a body of the received suspicious message or an attachment of the suspicious message contains a defined textual or binary pattern associated with a security threat; processing the received suspicious message according to the electronically stored rule to make a determination that the body of the received suspicious message or an attachment of the received suspicious message contains the defined textual or binary pattern associated with the security threat; and in response to the determination, associating the received suspicious message with a message group, the message group comprising of received suspicious messages having at least the defined textual or binary pattern in common, and each of the messages of the message group having been determined not to be a known simulated phishing attack based on an identifier or other message characteristic of the delivered message; and displaying a graphical representation of the message group in a user interface that enables an operator to perform batch operations on multiple of the suspicious messages in the group; and associating the received suspicious message with a message group, the message group comprising of received suspicious messages having at least the defined textual or binary pattern in common, and each of the messages of the message group having been determined not to be a known simulated phishing attack based on an identifier or other message characteristic of the delivered message; and displaying a graphical representation of the message group in a user interface that enables an operator to perform batch operations on multiple of the suspicious messages in the group; and removing one or more messages from messaging accounts associated with multiple users based on a matching of at least a portion of header information of the delivered message or at least a portion of metadata of the delivered message with the one or more messages from the messaging accounts associated with the multiple users.