Memorial walls have been set up at Taipei Main Station and Zhongshan’s commercial district after a deadly knife attack killed four people and injured nine last week. br br One of those killed was 57-year-old Yu Chia-chang from Taoyuan City. He tried to stop the attacker at Taipei Main Station, but it cost him his life. br br “I wanted to come remember him,” one memorial visitor told TaiwanPlus. “He saved a lot of people.