Following Tuesday's shooting on a New York subway train, the MBTA has beefed up security in Boston.
A gunman in a gas mask and construction vest set off smoke grenades and opened fire 33 shots in a rush-hour subway train in Brooklyn, wounding at least 10 people Tuesday, including five in critical condition.
A day after the shooting, 62-year-old Frank James was taken into custody. He's charged with a federal terrorism offense.
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The FBI Boston Division, Massachusetts State Police, Boston police and the Massachusetts Bay Transportation Authority said Tuesday that there was no known threat to Boston following the shooting, but officials are adding patrols as extra precaution.
MBTA Transit Police Chief Kenneth Greene said his department is taking extra steps like increasing patrols of regular officers as well as explosive detection teams, which will sweep for anything suspicious. Boston police will also be increasing their presence around subway stations in Boston. Officials are asking riders to report any suspicious behavior.
Experts say people should always be aware of their surroundings and have an exit strategy in mind ahead of time.
"Taking inventory of the egresses. Who am I in close proximity with? Am I trusting my gut? Am I feeling a sense of unease based on what's happening in the environment," retired Massachusetts State Trooper Todd McGhee said. "All these things are connected to our survival instincts."
Police found the key to a U-Haul van along with the weapon, extended magazines, a hatchet, detonated and undetonated smoke grenades, a black garbage can, a rolling car and gasoline. That key led investigators to James, who has addresses in Philadelphia and Wisconsin.
"Even though he's under arrest and in custody, the investigation is still fluid," McGhee noted.
McGhee said all of this evidence will be used to build the terror and violence case against James.
"It will be interesting to see if he was harbored by anyone, if he just concealed himself — there was discussion of possibly having a second vehicle after he got rid of the U-Haul van," he said.
The van was later found, unoccupied, near a subway station where investigators determined the gunman entered the train system. The investigation remains ongoing.