The TTC has increased security across its subway stations.

This comes after a terrorist attack at a Metro station in Brussels, Belgium early Tuesday morning.

“The TTC and its staff remain vigilant at all times,” said Brad Ross, TTC executive director of corporate communications, in a statement through Twitter. “We take our lead from law enforcement agencies, but ask our customers that, if they see or hear anything suspicious, to report it to a TTC employee or police: see something, say something.”

The heightened security is a concern for everyday passengers.

“It’s something that’ll sit in the back of my mind when I take the train for sure,” said Jermaine Williams, a daily TTC commuter.

“But for us to live our lives in fear would be to let them win and my values just can’t let me do that,” he added.

The attacks left at least 30 people dead and hundreds more injured.