Acting US Attorney General Todd Blanche says the motive of the suspected gunman is still under investigation, but that “preliminary” findings suggest he was targeting administration officials, “likely” including the president.

He tells NBC’s Meet the Press that investigators are looking at reports the alleged gunman assembled the weapon in the hotel, adding that the suspect “didn’t get very far”.

“He barely broke the perimeter,” Blanche says. He adds that the suspect likely travelled by train from LA to Chicago, and then to Washington DC.

He also confirms that the suspect will be formally charged on Monday.