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A legitimate Islamic State group propaganda video posted on social media last week features brief footage of the Las Vegas Strip while calling for lone-wolf terrorist attacks, and Las Vegas police are treating it as a credible threat, reports the Las Vegas Review-Journal .

The video is about 44 minutes long, which is unusual because Islamic State group propaganda videos are often much shorter, according to a representative with SITE Intelligence Group, a nongovernmental counterterrorism organization.

Similar, shorter Islamic State group propaganda videos are posted daily, the representative said.

The video featuring the Las Vegas Strip was posted last Wednesday on Telegram, a cloud-based instant messaging service, the representative said. It showcases the Islamic State group's newly developed weapons, and its final scene has a series of shots, including the Las Vegas Strip and New York's Times Square, while a narrator calls for general lone-wolf attacks in America, Europe and Russia.

The short clip of the Strip was determined to be 2015 footage, but Las Vegas police and their federal partners are taking the video seriously, Metropolitan Police Department Capt. Christopher Darcy, who heads the Southern Nevada Counter-Terrorism Center, said Tuesday.