The shooting in Orlando has security officials in Massachusetts keeping a close eye on the state's transportation systems in an effort to keep them from becoming soft targets.
Gov. Charlie Baker is calling for an increased police presence at MBTA stations and airports.
"History has taught us that public transportation systems are a soft target," Richard Sullivan, superintendent of MBTA police, said. "We have to be cognisant of that."
Commuters will notice tighter security this week including K-9 units in some of the lobbies. Amtrak said it is also working with local and federal law enforcement to keep passengers safe.
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"You'll see an increase in uniform presence at high volume stations during peak ride times you'll also see an increase in explosive detective units out there," Sullivan said.
Additional state troopers are on hand to monitor the terminals at Boston Logan airport. The extra patrols were visible outside the security checkpoints Tuesday morning.
"Thank God for the TSA and for them being strict," James Betancourt said, who was flying back to Orlando from Boston Tuesday. "I live right around the corner from there, so I want to know how my city has prepared and what they have in place to prevent it."
Security officials say it is a balance between creating an atmosphere of awareness and an environment of fear. Their efforts will continue across the state least through the rest of the week.