A line of luxury hotels linked to businessman and Republican presidential contender Donald Trump is investigating a possible credit card breach, Krebs on Security reported Monday, citing sources. The cybersecurity news site said financial industry sources noticed a string of fraud on customer credit cards used at the Trump Hotel Collection. The activity appeared on cards used in the past two to three months at properties including the Trump International Hotel New York, Trump Hotel Waikiki in Honolulu and the Trump International Hotel & Tower in Toronto, sources told the outlet.