Although there has been no specific threat, BART says its increasing security around stations in the recent wake of pipe bombs being sent to prominent political figures.
"I think it's a good idea, we all take BART to work, I want to feel safe and I want to come home," said BART rider Durla Kelleher.
Riders noticed extra BART Police Officers patrolling the Civic Center Station on Thursday.
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In a statement, a BART spokesperson said: "While no specific threats have been made against BART, we are boosting the visible presence of officers in our system including our K-9 units. As always we encourage our riders to contact BPD if they see anything suspicious. If you see something, say something."
BART won't say how long the heightened security measures will last.
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BART boosts security in wake of suspicious package scare