Boston police said they are closely monitoring the situation in London, England, where seven people were killed and another 20 injured on Saturday night.
"The BRIC (Boston Regional Intelligence Center) is continuing to monitor the situation in London at this time," Boston police said in a statement. "As always, we will ensure that we have adequate resources in place for all of our upcoming special events across the city."
Boston police said there are "no known credible threats at this time in the Boston area," but there will be increased patrols.
Massachusetts State Police said they are in contact with the U.S. Department of Homeland Security's National Operations Center and will receive updates if warranted.
"Our thoughts are with the London victims and emergency responders who again have been confronted by deadly extremist acts," state police spokesman Dave Procopio said.
Boston police and Massachusetts State Police have increased security at numerous major events including Boston Calling and Celtics and Red Sox games in the wake of the May 22 suicide bombing at an Ariana Grande concert in Manchester, England, that killed 22 people and injured dozens more.
Boston Mayor Martin Walsh tweeted Saturday evening, "Boston stands in solidarity with all Londoners. We send our prayers to the victims, first responders & all those affected. #PrayersForLondon."
Law enforcement in other areas of New England are also on alert. Connecticut State Police said members of its own regional intelligence center are vigilant, but stressed that "there are no known or suspected threats to the state of Connecticut regarding this event."