Thousands of people ride L.A.'s MTA subway system every day, including the above-ground light rail system. Most use the rail to commute to and from work.
There were no reports of any incidents Monday, but in the wake of Monday morning's suicide bombings in Moscow, Russia, authorities decided to beef up security.
In front of Union Station's Red Line Monday morning, deputies patrolled the walkway looking for anything suspicious.
"In light of the incident that happened in Moscow this morning, the sheriff's department have kind of beefed up security here on the rail system here in Los Angeles," said Rick Jager, a spokesman for the MTA. "It's strictly as a precaution. There have been absolutely no threats made to transportation properties here in the United States."
About a half a dozen K-9 units also patrolled platforms Monday.
Some deputies even went inside the trains to look for any unusual activity.
Michael Shub is originally from Russia. He says the number of people that travel the subway system daily in Los Angeles is miniscule compared to those in Moscow.
Asked if he felt safe riding the Metro Monday, Shub said, "Absolutely. This is completely different."
MTA officials say although there haven't been any attacks on the MTA system in recent years, security will always be tight. They say passengers are expected to do their part as well.
"It's very important that people be alert, be diligent when riding the system," said Jager. "If they see something that looks out of place, doesn't look quite right, they need to report that. They are our eyes and ears out there riding the systems."
Authorities intend to keep security elevated at least through the end of the week.