Beijing police have detained 39 people who brought prohibited knives into subways since security checks began on June 29.

Nearly 2 million passengers were subjected to checks from June 29 to July 13, and 3,400 forbidden articles were seized, said Liu Yong, a police officer of the Beijing Municipal Public Security Bureau.

Under Chinese law, passengers are banned from carrying dangerous items on public transport, including buses, subways, trains and aircraft. Offenders can be detained from five to 15 days.

Liu said most passengers were willing to undergo checks, and it took 15 seconds for a piece of luggage to be X-rayed.

Large luggage would be checked by X-ray machines, while smaller bags would be randomly checked. Sniffer dogs were also used for random inspections at some stations.

"Security measures are necessary with the current risks. I don't mind being delayed one or two minutes for security check," said Shan Qianwei, a tour guide from Yunnan Province, at the Wangfujing subway station.

Ninety percent of the 3,400 forbidden articles seized were flammable goods such as oil, paint, wine and thinner, which led some 2,000 passengers to be refused entry to the subway.

Beijing has five subway lines with 140 km of track, moving millions of passengers every day. It plans to add three new subway lines this year to expand the system to 200 km.

(Xinhua News Agency?July 14, 2008)