A man has been arrested at the Trump International Hotel in Washington DC after weapons were discovered in a vehicle.
The US Secret Service and local police responded to a report of a "potential threat against Secret Service protectees" in the early hours of Wednesday morning.
Officers and agents had received information from a 'concerned citizen' and security staff at the hotel.
A man was located at the hotel, while a "semi-automatic assault style rifle" and a handgun were found in a vehicle.
An explosive ordnance unit examined the vehicle, but found no hazardous materials.
The man - who police say had checked himself into the hotel - has been arrested and charged with illegal possession of firearms.
The Secret Service has insisted none of its protectees were at risk.
Washington police chief Peter Newsham said a tipster coming forward with the information had 'averted a potential disaster' in the US capital.
Brian Ebert of the Secret Service thanked local law enforcement, adding: "This investigation is still new and ongoing.”