Authorities Believe They Identified Mystery Man in Brussels Bombings

VIDEO: Belgian police released a photo taken from surveillance footage that shows three men pushing baggage carts.PlayABCNews.com
WATCH Brussels Terror Attack: US Authorities Now Believe They Know Who the Mystery Suspect Is

Authorities believe they have identified the mystery man wearing the light-colored jacket in a photograph with two of the bombers at the Brussels airport, according to a U.S. official.

The name was not released, but it was already in U.S. terrorism databases at the time of the bombings, the official said. Another official said Belgian authorities are confident they have identified the individual but are urgently working to capture the subject and confirm his identity.

U.S. officials have confirmed that the brothers allegedly involved in the Brussels terror attacks, Khalid and Ibrahim El Bakraoui, were already in U.S. terrorism databases as well. Both were believed to be suicide bombers in the attacks.

PHOTO: Ibrahim El Bakraoui is pictured in a July 2015 image taken by Gaziantep police. Right, This photo accompanied an INTERPOL Red Notice for Khalid El-Bakraoui.Haberturk newspaper via AP | INTERPOL
Ibrahim El Bakraoui is pictured in a July 2015 image taken by Gaziantep police. Right, This photo accompanied an INTERPOL Red Notice for Khalid El-Bakraoui.

In recent weeks and months, there has been consistent chatter about other terror plots planned for Europe, with specific locations and targets being discussed, a senior intelligence official told ABC News. New attacks could come at any moment, the official added.

PHOTO: This notice about Najim Laachraoui was posted online by the Belgian Federal Police in November 2015.Belgian Federal Police
This notice about Najim Laachraoui was posted online by the Belgian Federal Police in November 2015.

A third suspect, 24-year-old Najim Laachraoui, was on the run from police when he allegedly detonated one of the bombs at the airport. Belgian authorities posted a wanted notice for the Moroccan native the day of the coordinated Paris attacks in November that killed 130 people.

Laachraoui was believed to be a suicide bomber in the attacks as well.

ABC News' Pierre Thomas contributed to this report.