European private equity firm PAI Partners said it agreed to sell air cargo handler Swissport International Ltd to China's HNA Group Co Ltd for 2.7 billion Swiss francs ($2.8 billion). Reuters had earlier this month reported that HNA, the owner of China's Hainan Airlines, was interested in buying Swissport. The deal, which is expected to occur around the end of the year, marks PAI's exit from the ground handling and cargo services company it bought less than five years ago for 900 million Swiss francs.  Swissport, which operates in 48 countries, generates operating revenue of 3 billion Swiss francs and handles 4.1 million tons of cargo a year, PAI said in a statement.