The Islamic State group has no “credible” plan to attack the New York City subway system, Mayor Bill de Blasio said Thursday. The mayor’s remarks came after Iraqi Prime Minister Haider al-Abadi said that Iraq had received intelligence that the militant group was planning an attack on both the Paris and New York City transit systems.

"I have a simple message for all New Yorkers. There is no immediate, credible threat to our subway system," de Blasio said at a press conference Thursday.

The Federal Bureau of Investigation and New York City Police Department also found no new evidence of a credible threat against New York City, NBC News reported.

"The first we heard of this threat is when the press began reporting it," an intelligence official told NBC news.  

In order to prove to New York City residents that they had nothing to fear, de Blasio rode the subway to a major transit hub before giving his press conference. New York Gov. Andrew Cuomo also took public transit in an attempt to discredit any claims that the city was under threat from the militant group formerly known as the Islamic State of Iraq and Syria.

"The New York City subway system is safe. Go about your business — be prudent, everyone can be helpful, the expression 'if you see something, say something,' is truer now more than ever," Cuomo said, echoing de Blasio.

Despite reassurances from New York leaders, there will be an uptick in the police presence in transit stations around the city.

"You are going to see a greater police presence than you have seen before," Cuomo said, according to Reuters. "Don’t be alarmed. If anything, that should be comforting."

The increase in law enforcement is also a response to Khorasan, an al Qaeda-affiliated militant group in Syria that U.S. intelligence officials said they consider more of a direct threat to the U.S. than ISIS.  

Al-Abadi told a United Nations General Assembly meeting in New York City Thursday that the Iraqi government had captured several ISIS militants who had confessed a plan to attack the transit system.

"I'm receiving accurate reports from Baghdad that there were arrests of a few elements and there were networks from inside Iraq to have attacks ... on metros of Paris and U.S.," al-Abadi said at the U.N. General Assembly meeting. "They are not Iraqis. Some of them are French, some of them are Americans. But they are in Iraq."