SHANGHAI (AP) -- A quarter of the police in Shanghai began carrying guns during routine patrols for the first time this week as part of a China-wide boost in police firepower following a deadly mass knifing blamed on Xinjiang separatists.

Ordinary police in China generally don't carry firearms, and none of the officers patrolling the train station in the southwestern city of Kunming on March 1 was armed when at least five assailants began rapidly hacking at victims with long knives.

Before armed reinforcements arrived to subdue the attack, the assailants were able to kill 29 people and wound more than 140, raising concerns about the safety of crowded public places and fears that militants from the far western region of Xinjiang may seek to strike soft targets farther east.

China plans to introduce armed police patrols in several major cities, and started last Thursday in the central city of Xi'an and over the weekend in Shanghai and Qingdao. In Shanghai, about 1,000 of the 4,000 police have undergone special training _ including psychological _ to carry 9 mm pistols and started carrying them Sunday, the city government said on its website.

China has very little gun violence and firearms are difficult to obtain, making the notion of armed patrols a novelty that drew mixed feelings among some residents.

Zhang Liqi, a decoration designer in Shanghai, said Monday that she believes the change is good and in line with international norms, but fretted that guns could be stolen from officers and could fall into criminal hands.

Her colleague, Liang Jing, 33, was thrilled about gun-toting officers though she hadn't seen any yet. "Wow, so cool! They were cool before but now they're even cooler and can do the job of protection even better!" Liang said, although she added that she had misgivings about some officers carrying guns.

"Now they have the power to decide one's life.  If some of the police officers' personalities are not so good, then I'm kind of worried. Will they feel free to shoot? As far as I know from cases I have read online, police might hurt people," she said.

Government authorities have blamed the Kunming attack on separatists from Xinjiang _ where some members of the Muslim Uighur ethnic minority have waged a low-scale insurgency for years _ but have provided few details of their evidence. Some Uighur advocates have warned that the attack may worsen what they call oppression of the Uighurs in Xinjiang.

The state Public Security Ministry said the campaign for armed police patrols also would extend to the southern cities of Changsha and Kunming, as well the main cities in the restive ethnic regions of Xinjiang and Tibet, although those areas already have seen tight security crackdowns that include armed paramilitary police.