Owners of the financially beleaguered 713-room Pittsburgh Hilton, the city’s largest downtown property, received word from Hilton Hotels & Resorts on Thursday that the lodging company is ending its 51-year-old franchise agreement. The hotel was deflagged due to violations of the agreement, said a Hilton spokesperson. The following day, property mortgage holder Black Rock Financial Management Inc. filed a complaint in an attempt to foreclose on the hotel, according to the Pittsburgh Tribune-Review. The hotel continues to operate normally, said an on-site catering and events manager, who added that the current problems are strictly between the ownership and Hilton and are not affecting day-to-day operations; negotiations between the two parties are ongoing, she said, and the hotel will continue to use the Hilton name until it is specifically directed otherwise. The hotel’s reservation system has been down since Friday, as Hilton removed the property from its system, but hotel management said it was in the process of implementing a new management system, which they hoped to have up and running by the end of the day Tuesday.