Brussels Attacks Put United States On High Alert

While American authorities reiterated that there was no credible threat to the United States, law enforcement officials from Los Angeles to New York were taking extra security precautions following attacks in Brussels that left dozens dead.

Airports across the country accommodated canceled flights and beefed up security, while subway systems in major metropolitan areas were protected with armed security guards.

“We will do whatever is necessary to support our friend and ally Belgium in bringing to justice those who are responsible,” President Obama said from Cuba, where he was in the middle of a historic visit to the country.

“The world must unite. We must be together regardless of nationality, or race, or faith, in fighting against the scourge of terrorism.”

• Brussels Attacks: Bomb Explosions Kill Dozens, Injure Scores More

Within hours of the attacks, the New York Police Department announced it would deploy counterterrorism forces throughout the city, especially to "crowded areas and transit locations."

All flights were canceled Tuesday between NYC-area airports and Brussels.

New York Gov. Andrew Cuomo announced around 10 a.m. EDT that he had sent State Troopers and 400 members of the National Guard to the NYC area and had ordered the Port Authority of New York and New Jersey and the MTA to fill airports and rail stations with extra security.

Scott Ladd, a Port Authority of New York and New Jersey spokesman, said Port Authority Police were increasing their anti-terrorism presence at Newark Liberty, JFK and LaGuardia airports.

“High visibility anti-terrrorist patrols are being added to the PATH system and the World Trade Center," Ladd said.

It was a similar story in Los Angeles, with heightened security on the city's Metro lines and at LAX.

In the nation's capital, K9 patrols swept through D.C. Metro stations, and area flights to Brussels were canceled.

Boston also added security to transportation centers.

"While there has been no credible threat to MA, security has been strengthened for our public transit systems and airports," Massachusetts Gov. Charlie Baker said in a series of tweets. "Patrols have been directed to increase presence in areas near transportation centers in the state. As always, a multi-layered plan is in place at the airports and seaports."

The NYPD used the opportunity to oppose a city funding cut.

"These attacks come at a time when the federal government has proposed cutting terrorism funding to New York City by roughly 90 million dollars," Stephen P. Davis, deputy commissioner of public information for the NYPD, said in a statement.

"Any cut in terrorism funding to New York—to what is widely recognized as the nation’s top terror target—would be irresponsible."

Image via NYPD

Simone Wilson, Greg Hambrick, Deb Belt and Tom Davis contributed to this report