Beijing has launched security checks in its subway system as the city steps up all-round services for the upcoming Olympic Games.

Subway passengers will face checks by scanners, police, dogs and 3,000 specially trained security guards.

Guns, ammunition, controlled knives, flammable material, explosives and radioactive and poisonous articles will be the focus of the checks.

Police say passengers would have to drink bottled water and other beverages they carried into the subway if security scanners and police dogs could not identify them.

All subway stations will be subject to the checks until September 20, as part of the security for the Olympics and Paralympics.

In related news, the city has also set up a call center to resolve Olympic-related inquiries.

Zhai Qin is head of the center.

"If you have any questions concerning how to reach the venue and what items are allowed in the venue, just dial 12308."

The call center operates 15 hours a day from 7 am to 10 p.m. during the Olympics.

Information is available in 11 languages, including English, French, Russian and Japanese.