If you select the email(s) by clicking the tick-boxes in the column on the left, then click the Spam button (with shield icon) in the bar across the top of the inbox, it'll move them into the Spam folder and should subsequently recognise similar emails as spam. Then you can delete them with the trashcan icon that appears when you hover over Spam in the navigation column.
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If you select the email(s) by clicking the tick-boxes in the column on the left, then click the Spam button (with shield icon) in the bar across the top of the inbox, it'll move them into the Spam folder and should subsequently recognise similar emails as spam. Then you can delete them with the trashcan icon that appears when you hover over Spam in the navigation column.