Six HSBC workers were fired on Monday for pretending to be Islamic State (IS) militants carrying out a beheading.The seven-second video showing a man dressed in an orange jumpsuit and five other men around him, one of them holding a fake knife, was filmed during a team-building exercise and posted on Instagram.The employees were members of the bank's legal division in Birmingham, The Sun reported.HSBC apologised for its workers' behaviour, adding the company would not tolerate it."As soon as The Sun brought this video to our attention we took the decision to sack the individuals involved."This is an abhorrent video and HSBC would like to apologise for any offence."