BEIJING, May 12 (Xinhua) -- More police officers and subway staff were put on duty in Shanghai on Monday to handle passenger peak hours -- the first work day after new security-check channels went into operation over the weekend.

    Metro police said they would also beef up the number of patrol officers and sniffer dogs to carry out increased random checks among the crowd so as to relieve pressure on the luggage checkpoints near station entrances, English-language Shanghai Daily reported Monday.

    The increased workforce was expected to help speed up security checks during work day rush hours to ensure smooth traffic flow as well as improve Metro safety, police were quoted as saying.

    Officers and subway employees working at the new checkpoints have undergone professional training and will try their best not to affect commuters, police said.

    They asked passengers to cooperate with checking staff.

    About 260 inspection areas for scrutinizing luggage security were opened at all 161 Metro stations in Shanghai, China's commercial hub and most populous city, on Saturday.

    The new channels operated smoothly and did not hold up passenger flows at the weekend.

    At hub stations, such as the People's Square and Zhongshan Park, most luggage inspections were each completed within about 30 seconds.

    Bags and suitcases of medium and large sizes will be subject to examination at the special checkpoints before they can be taken into a station. Metro safety rules state that Metro workers and police have the authority to order passengers to open any carry-on for a security check.

    Shanghai Port International Cruise Terminal also launched the luggage inspection system on Saturday afternoon to prevent combustible and dangerous goods from being carried onto passenger liners. It's the first time the cruise ship terminal has adopted such a security-check system.

    Three were killed and 12 others injured in a bus fire in the city last Monday, which police said was caused by flammable oil-like material carried aboard by a passenger. Security check was then beefed up on city buses following the deadly accident.