If carrying luggage onto the Metro, prepare to be inspected. That new police officer hanging out drinking tea is manning one of the new security check panels and Fido is sniffing for more than just his next Scooby snack. Medium to large bags and suitcases are now subject to inspection, the aim being to prevent dangerous or combustible items from being carried onboard, and sniffer dogs are also being employed (for a low wage we imagine) at some of the busier stations. Authorities are particularly watching for items such as gasoline, oil paint and glue. If a passenger is found to be carrying dangerous substances, they will be asked to leave the Metro and take a non-public form of transportation. While the move is said to be aimed at ensuring greater security for the Beijing Olympic games this coming August, the timing of these new security checks coincides with a recent explosion on a public bus which killed three people, an explosion authorities claim was caused by a flammable substance.