Some New Yorkers woke up to a disturbing scene this week - hundreds of dead birds around the city's World Trade Center.

The upsetting discovery was made by Melissa Breyer, a volunteer who each day checks for animals injured from flying into skyscrapers. Her daily checks are to help out New York City Audobon's Project Safe Flight, a group whose aim is to help birds migrate safely through the Big Apple. Sadly, a whopping 261 birds were not able to safely migrate on Tuesday morning.

Breyer told Vice, "It was 6:15am when I got there, so the sun hadn't fully risen, but you could still see them: there were these dark little shadowy lumps of bird. It was like a scene out of a horror film."

She shared photos of what she saw on Twitter, noting that while many birds perished because they flew into the building, she was able to bring 30 injured birds to the wildlife rescue service Wild Bird Fund. She also warned her fellow New Yorkers to "be careful where you step."