WASHINGTON (AFP) - US President Barack Obama on Saturday called the three Americans who overpowered a gunman on a Paris-bound train and congratulated them on their "extraordinary bravery," the White House said.

Spencer Stone, Aleksander Skarlatos and Anthony Sadler tackled, disarmed and subdued the assailant Friday after he fired shots and burst into their railroad car with an assault rifle.

The Moroccan suspect has been identified as 25-year-old Ayoub El Khazzani, who was first flagged by Spanish authorities as a potential extremist and had reportedly travelled to Syria.

Stone, who is a member of the US Air Force, was badly cut in the struggle and was still in the hospital Saturday recovering from his wounds.

Obama called the three "to commend and congratulate them for their courage and quick action aboard their Paris-bound train last night," White House spokesman Eric Schultz said.

"The President expressed his gratitude to these three individuals for their heroic actions forestalling an even greater tragedy," Schultz added.

"The President wished airman Stone a full and speedy recovery, and expressed how proud all Americans are of their extraordinary bravery."

The three are childhood friends who were on a European trip together after Skarlatos' recent deployment to Afghanistan as a member of the Oregon National Guard.