Caltrain officials evacuated a train at the Menlo Park station Monday afternoon because of a suspicious piece of luggage left on a train.
The incident was first reported at 3:05 p.m., according to Caltrain spokeswoman Tasha Bartholomew.
Police and a bomb squad resonded to the scene to investigate.
Caltrain tweeted the incident was given an all clear just before 4 p.m.
Bartholomew said Caltrain is taking all necessary precautions and that security is heightened this week because of the upcoming Super Bowl 50 at Levi's Stadium in Santa Clara on Sunday.