Three explosives detection canine teams have begun patrols of Maryland's bus and rail systems as part of expanded national efforts to secure mass transit, the Transportation Security Administration (TSA) said Wednesday. Maryland Transit Administration (MTA) and Maryland Transportation Authority (MdTA) officers started using three German Shepards to sniff for explosives on MARC, MTA buses and light rail vehicles. The officers participated in a TSA training course in San Antonio, Texas, where they learned how to handle the dogs. In addition to handler skills, the officers learned explosives safety, and safe handling and accountability of explosives canine training aids. Launched in August 2005, the mass transit canine initiative looks to expand on TSA's training program, which involved 400 dogs at 77 airports nationwide. The canine program, a partnership between the federal government and local transportation entities, pays to train the dogs, provides in-depth training for the handler, and partially reimburses the participating agency for costs associated with the teams, such as salaries and veterinary care. Baltimore's MTA and MdTA are among the first systems in the country to have all three teams on the job as part of this program.