New York (CNN) -- Gotham's top cop on Tuesday said authorities are looking into the possibility that an Egyptian writer may have been responsible for an online posting that pictured a New York cityscape with the words "Al Qaeda. Coming Soon Again in New York."
"The use of language indicated that," said New York Police Commissioner Ray Kelly. "Its many different dialects in Arabic and our analysts thought that this was Egyptian in nature."
He said that the graphic image, which surfaced Monday on a few jihadist Web forums and featured the words in the English, did not coincide with any specific online chatter about a potential threat and that it was unclear whether one or multiple individuals was responsible for the posting.
"The Internet is, as we used to say, is the new Afghanistan," Kelly told reporters. "That's where training happens. That where radicalization happens. It's become a very valuable tool to the terrorists."
Still, FBI spokesman J. Peter Donald said that while his agency was also investigating, "there is no specific or credible threat to New York at this time."
"The NYPD Intelligence Division's cyberunit is investigating the origin and significance of the graphic," said police spokesman Paul Browne said earlier Tuesday. "Until more is learned about their origin, we take all threats against New York City seriously."
The posting comes just months after the 10 year anniversary of the 2001 terrorist attacks in New York, Pennsylvania and Washington.