Police have arrested a man who allegedly murdered six people, including four colleagues, a driver and a sentry, in Shanghai, the municipal government said Sunday. The 62-year-old suspect, a man surnamed Fan, beat a colleague surnamed Zhang to death at 5 p.m. Saturday at a chemical factory in the city\'s Baoshan District, the government said. The fatal beating was allegedly triggered by a financial dispute between Fan and Zhang. He then took a hunting rifle hidden in his dormitory and asked a driver to drive him to a different district. He gunned down the driver on the way and then drove the vehicle back. He then killed a guard at the gate of a nearby military barracks and took the soldier\'s gun. After returning to the plant, he killed another three people with his rifle. He was captured by police who were at the factory investigating the case at 11:15 p.m. Saturday. Police are still investigating the case. The Ministry of Public Security on Sunday ordered police authorities across the nation to step up street security and resolutely stop violent crime.