The officers stood watch along side passengers on train platforms.
It's all part of increased security at transit stations in Southern California and the United States, in light of two suicide bombings in the subway in Moscow Russia Monday. Two female suicide bombers blew themselves up on packed subway cars in Russia, killing at least 38 and injuring dozens more.
Here in Los Angeles the Sheriff's Department is contracted to provide security for Metrolink trains and subways.
"There will be an increase in our patrols and our observations. We're always on high alert in the Los Angeles region because we have sensitive sites, but there is no specific threat that is related to the L.A. transit or the L.A. area," according to Steve Whitmore of the Los Angeles County Sheriff's Department.
Despite there being no specific threats to the Los Angeles area, law enforcement officials aren't taking any chances.
Police dogs were directed to search trash cans at train stations, which have been used as hiding places for explosives in other parts of the world. The bomb-sniffing canines were also taken onboard trains to search for anything suspicious that may have been left behind.
Mayor Antonio Villaraigosa took the opportunity to state again his reasons for wanting to increase the number of police in a time of budget deficits and layoffs.
"One of the reasons why I've said we've got to grow our police department is we've got to maintain the size and scope of our Homeland Security efforts," said Antonio Villaraigosa, Mayor of Los Angeles.