Beijing has updated its list of prohibited items for subway passengers, and has also vowed to enhance security checks by using more advanced equipment, the Beijing Morning Post reported Friday.

Passengers are now allowed to carry four cigarette lighters at most, according to the list.

Chinese baijiu, a flammable, pungent white liquor, is also on the list for the first time. Subway passengers can take no more than 2,000 milliliters of baijiu, a hugely popular drink in China.

Also new on the list are matchs and flowery water used to avoid heat-rash or deter mosquitoes. Passengers are not allowed to carry 10 or more boxes of matches (200 or more matchsticks) on a subway train.

The list also makes more demands regarding various tools that can be taken onboard, expanding the list of banned items to kitchen knives, cleavers, some knives used in tailoring, and hammers.

Tan Quan, the deputy director of the Beijing Police Public Traffic Division, says security equipment will be upgraded to enhance accuracy and speed to cope with large numbers of passengers.

He says the ban list is stricter than that for train passengers, as the subway operates in a closed space and the number of passengers reaches close to 10 mill.