NEW YORK (CBSNewYork/AP) — The NYPD said it is “closely monitoring” the developments of a mass shooting at a Orlando nightclub and said police are on alert as the investigations unfolds.

As WCBS 880’s Stephanie Colombini reported, Mayor Bill de Blasio said there was no credible threat against the city. But he said the NYPD was in close contact with federal law enforcement and has been placed on high alert.

“So you’ll see a lot of additional police presence on the streets of the city, you will see additional police presence in some of the heavy trafficked areas of our city today,” de Blasio said. “You’ll see police presence in front of some key LGBT community institutions.”

De Blasio said the shooting in Florida was an attack on the nation’s values of tolerance and inclusion. He called on New Yorkers to join in solidarity with the people of Orlando and the LGBT community as a whole, as investigations continued.

“I want to just offer my solidarity to the people of Orlando and to all of our brothers and sisters in the LGBT community in Orlando, in New York City, and all over the world who are feeling the pain of this attack,” de Blasio said.

The NYPD said Sunday that is in contact with law enforcement authorities in Florida and the FBI.

Speaking at the Puerto Rican Day Parade, New York City and state leaders outlined upcoming security measures including the extra deployment of cops and the NYPD’s 500 member Critical Response Command, CBS2’s Scott Rapoport reported.

Gov. Andrew Cuomo also decried gun violence as he addressed the shooting during. He also spoke during the parade.

“The gun violence is just getting worse and worse and worse,” Cuomo said. “It’s going to be a sad fact in history when we look back and we see how many people we lost to gun violence.”

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“Meanwhile the NYPD has placed our Patrol and Counter-terrorism resources, including CRC, SRG and ESU personnel, on alert pending further information,” the NYPD said in a statement.

The NYPD said it is “constantly working with law enforcement and community partners to counter terror.”

“New Yorkers should know that the NYPD has more than 500 officers dedicated solely to terror response, hundreds more to the prevention of incidents,” police said.

In a Twitter post, the department also said “Our prayers go out to those affected by the Orlando shooting.”

The attack early Sunday morning at Pulse Orlando, a popular gay dance club, left 50 people dead and 53 more injured in what is now being called the worst mass shooting in U.S. history.

Officials said they’re investigating the incident as an act of terrorism.

NYPD Chief of Department James O’Neill says there will be an increased police presence at LGBT institutions, nightlife venues and crowded areas, WCBS 880’s Colombini reported.

“I will be working with the LGBT community not just in Manhattan but in the outer boroughs also to make sure we deploy properly to make people not only safe but to feel safe throughout the city,” O’Neill said.

New Jersey officials say they’re not planning any extra security measures in the state following the incident, but they are reminding residents to remain vigilant and report any suspicious activity to authorities.

State police say New Jersey homeland security officials have not detected any credible threats in the wake of Sunday’s shooting in Orlando. But they say authorities continue to closely monitor the situation.

Law enforcement authorities in the state’s major cities and at the Jersey Shore — home to many gay clubs — said they had no immediate plans to beef up security or impose new policies.

Law enforcement sources told CBS News the gunman has been identified as Omar Mateen, 29, a U.S. citizen from Port St. Lucie. Mateen was born to Afghan parents. CBS News reports Mateen has no apparent criminal history and that authorities are investigating whether he had ties to Islamic terrorism.

The Islamic State of Iraq and Syria has claimed responsibility for the shooting, CBS News reports. The terror group’s news organization, Aamaq Agency, said the attack was “carried out by an Islamic State fighter.”

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