Millions of New Yorkers and tourists are expected to line the streets on Thursday for the Macy's Thanksgiving Day Parade, more than a week after Islamic State, also known as ISIS or ISIL, released a video showing images of New York juxtaposed with a scene depicting a suicide bomber preparing for an attack.

The group has claimed responsibility for the simultaneous attacks in Paris on Nov. 13 that killed at least 130 people at a soccer stadium, a concert hall, bars and restaurants.

But New York City officials have a simple response: Don't be scared.

"We can't change who we are," Mayor Bill de Blasio said at a public event on Thursday, urging people not to alter their daily lives. "Do we want to play their game? Do we want to give in to them?"

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While they haven't given much operational detail, de Blasio and Police Commissioner William Bratton said thousands of police officers will be out in force on Thursday during the parade, which typically draws millions to the streets of Manhattan.

Security efforts will be bolstered by a new counterterrorism unit, Critical Response Command, that includes more heavily armed officers. Another unit created this year to respond to large protests and other incidents requiring more manpower will also assist patrol officers.

Bratton said people should feel confident that the department is able to handle any threat. His own grandchildren are visiting New York for the first time next week and will attend the parade, he said.

"Celebrate, be aware, but do not be afraid," he said at a news conference this week to address the Islamic State video. "The NYPD will protect you."

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City officials also said the footage shown in the Islamic State video is old and that there is no evidence of a "specific and credible threat" to New York.

Holly Thomas, a spokeswoman for Macy's Inc., also offered reassurance. "As with any public event in New York City, security elements are extensive - from the very visible presence of law enforcement officers to wide-ranging behind-the-scenes security operations," she said.