There is ongoing concern within the New York Police Department over an Iranian-sponsored terrorist attack in New York City, due to the area’s large Jewish population, Commissioner Ray Kelly said Tuesday, according to The New York Post.

“We’ve been concerned about Iran for a while, and I think the history of those events throughout the world since January give us cause for concern,” Kelly said during a NYPD SHIELD conference, a public-private partnership that provides counterterrorism training in an effort to protect New York City from terrorist attacks.

Kelly said that the ongoing tensions between Iran and Israel is a particular area of concern, given New York City’s large Jewish population, which numbers at approximately 1.5 million—the largest Jewish population in any city worldwide outside of Israel.

Kevin Yorke, a lieutenant in the NYPD’s Intelligence Division, added that a possible Israeli strike against Iran’s nuclear facilities may lead the regime to attack the U.S., particularly New York.

“Within the last year, we’ve seen a worldwide increase in incidents involving the stockpiling of explosives, the surveillance of targets, and a number of very significant plots and attacks,” Yorke said, according to The Post.

He added that the increase in activity is in direct relation to Iran’s nuclear-weapons program and tensions surrounding the regime’s persistent calls to annihilate the State of Israel.

“Obviously if there’s any action involving Israel and Iran we have to be very cognizant of the potential of retaliation here in New York City,” he said.