China's stability obsessed ruling Communist Party, always jittery about any threats to its rule, has been alarmed by a series of incidents in recent months, including a knife attack at a train station in the city of Kunming blamed on militants from the far western region of Xinjiang this month.
"The ministry (of public security) said that it will carry out armed patrols and take timely measures to handle violent criminals," Xinhua said.
"The ministry urged public security organs at all levels to increase work efficiency and further improve the emergency command mechanism in order to fight crime," it added.
Police should also "enhance prevention and control" over busy areas like stations, airports, schools, hospitals and tourist attractions, Xinhua said.
Chinese police generally do not carry guns and gun crime in rare in a country with tight controls on firearms. Most violent crime happens with knives, or homemade weapons like small bombs made of fertilizer or other easily obtainable chemicals.
Last week, police shot dead a man who went on a rampage with a knife in central China, killing five, after a dispute between market vendors got out of control.
China's leadership is highly sensitive to issues of unrest from separatist groups in the northwestern Xinjiang region to dissidents organising through booming social media networks.
The government typically spends more on domestic security than even on its fast-growing military budget, though it unusually did not publicize the overall figure this year.
Police in major cities such as Beijing and Shanghai will increase surveillance, while Kunming, the site of the recent attack, Xinjiang capital Urumqi and Tibetan city Lhasa will also see security tightened, Xinhua said.
China's intense focus on domestic security has at times drawn criticism from international rights group, who say authorities use it to suppress anyone who rattles the country's tightly controlled political system.