Single Bomb Threat Grounds 2 Planes at JFK

Both planes were searched.

"Earlier this evening, another airline received a threat regarding Delta flight 468. Delta currently operates two aircraft under that specific flight number -- San Francisco to New York-JFK which is currently on the ground at New York-JFK and New York-JFK to Tel Aviv, currently in the boarding process," Delta said in a statement.

"Proper security procedures are being followed for both aircraft. Delta has passed this information along to federal authorities."

Passengers were bussed from the tarmac to the terminal while the planes were searched. Both planes were given the all clear to take off, the FBI said in a tweet.

Andrew O'Boyle, a passenger on the arriving plane, said everything was going smoothly until the plane landed. Then the plane was surrounded.

"It's really quite surreal when something like that happens. You don't know how you’re going to react or everyone around you is going to react," he told ABC News.

"I'm just happy everything went smoothly and we're all safe."