NEW YORK (CBSNewYork/AP) — The NYPD is on alert following a threat against the United States purportedly by Somalia’s al-Qaida-linked rebel group al-Shabab.

A video released over the weekend urged Muslims to attack shopping malls in the U.S., Canada, Britain and other Western countries.

The threat came in the final minutes of a more than hour-long video in which the extremists also warned Kenya of more attacks like the September 2013 assault on the Westgate Mall in Nairobi in which 67 people were killed.

The masked narrator concluded by calling on Muslims to attack shopping malls, specifically naming the Mall of America in suburban Minneapolis, as well as the West Edmonton Mall in Canada and the Westfield mall in Stratford, England.

The authenticity of the video could not be immediately verified by The Associated Press.

Following the threat, the NYPD issued a statement saying they were aware of the video and have taken steps to ensure the safety of New Yorkers.

“We are aware of the recent ‘threat’ and we have been in touch with our international and federal liaisons. Although there is no direct threats against New York City, as well as no credible intelligence of such, we have taken appropriate precautionary measures, such as alerting our Critical Response Vehicles and our ‘Hercules’ (special counter-terrorism) Teams. This is something we regularly do in response to terror incidents/threats in other areas of the world that may impact New York City,” the statement from NYPD Deputy Commissioner of Public Information Stephen Davis said.

New York Rep. Peter King said since the Westgate Mall attack, malls all over the U.S. have stepped up their security, CBS2’s Dave Carlin reported.

“We have to really increase security at the malls and just as importantly we have to get intelligence,” King said. “Because if they make it to the mall, unfortunately they are going to succeed; we have to stop them before they get there.”

New York mallgoers told Carlin they didn’t see any reason to be fearful, just vigilant.

“Anybody could be targeted at any time,” said Idris Ellams, of Roackaway Park.

“That’s just a fear tactic,” said another shopper.

“I’m just going to go about my business every day. I’m not going to let them scare me,” James Campo, of Elmhurst said.

U.S. Department of Homeland Security Secretary Jeh Johnson called the video “the new phase” of the global terrorist threat and warned the public to be vigilant.

“These groups are relying more and more on independent actors to become inspired, drawn to the cause and they’ll attack on their own,” Johnson said, speaking on CNN’s “State of the Union.”

When asked about the threat against the Mall of America in particular, Johnson said “Any time a terrorist organization calls for an attack on a specific place we’ve got to take that seriously. What we’re telling the public is you’ve got to be vigilant. — There will be enhanced security there that will be apparent, but public vigilance, public awareness and public caution in situations like this is particularly important.”

The Mall of America, one of the nation’s largest, said in a statement that it was “aware of a threatening video which includes a mention and images of the mall,” and said extra security had been put in place.

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