Local law enforcement agencies across the United States confirmed Tuesday they were taking precautions after the explosion ripped through an Ariana Grande concert in the U.K., killing at least 22 and injuring dozens more.
Both the New York City Police Department and the Los Angeles Police Department tweeted they were going to keep an eye on events out of England. Police officials said they were not aware of any credible threats to the public but had the resources in place to respond to any emergency.
Police in Boston said in a statement that they "increased patrols at concert venues in and around the city." They called on people in Boston to be extra vigilant if they see something suspicious.
The Washington Metro Police Department asked the public to remain "vigilant" as they monitored reports and events, according to a statement.
"As the law enforcement agency responsible for protecting the nation's capital, we are actively working in coordination with our local and federal law enforcement partners, as well as homeland security agencies to ensure the safety of all visitors and residents to the District of Columbia."
Investigators in England announced that the explosion would be treated as a terrorist incident "until proven otherwise."
In the wake of the attack, the Department of Homeland Security said there was "no specific credible threat" involving music venues in the U.S., but that the public "may experience increased security" around public places and events. Madison Square Garden, the multi-floor arena in in midtown Manhattan, announced on Tuesday it will be increasing security for future events, according to a company statement.
"Madison Square Garden has increased security measures, including a greater police presence, and is continuing to work closely with local law enforcement to ensure we remain informed of any potential concerns."
Fox News' Jake Gibson and Kathleen Foster contributed to this report.
Edmund DeMarche is a news editor for FoxNews.com. Follow him on Twitter @EDeMarche.