Three people were killed and 15 others injured in a knife attack at a supermarket in the eastern Chinese city of Shanghai on Tuesday, according to local police. The suspect, a 37-year-old man, was apprehended at the scene by police. Initial reports indicated that 18 people were injured and taken to hospital. Three of them later died. Police said that the suspect may had been motivated by financial difficulties and sought to express his frustrations through the attack, adding that investigations were ongoing. Knife attacks have become a recurring issue in China. In mid-September a Japanese boy …