Bryan Adams' vintage guitar and other instruments were marked with green indelible marker by customs officials at Cairo International Airport. The incident was likely a customs clearance identification, but Adams expressed concern for the fragile exterior of his 1957 Martin D-18 guitar. This is not the first time his instruments have been tagged by airport officials, as he alleged in 2015 that one of his guitars was written on by Air Canada staff. Adams is currently on a world tour promoting his 13th studio album, 'Get Up.'