The man, thought to be in his early twenties, was carrying what appeared to be a shotgun and a fuel can as he tried to breach the secure perimeter, according to the agency. President Trump was not at the Florida resort at the time, despite regularly spending weekends there, and was instead at the White House.

Officials have not yet released the man’s identity. The Secret Service said he was seen near the north gate shortly before 01:30 local time on Sunday. Agents, supported by a Palm Beach County sheriff’s deputy, opened fire after he failed to follow instructions and raised the weapon,

"At 1.30 this morning, the security detail detected that an individual had made his way into the inner perimeter of Mar-a-Lago. A deputy and two Secret Service agents on the detail went to that area to investigate," confirmed Rick Bradshaw, the sheriff of Palm Beach County.

"They confronted a white male that was carrying a gas can and a shotgun. He was ordered to drop those two pieces of equipment that he had with them at which time he put down the gas can, raised the shotgun to a shooting position.

"At that point in time, the deputy and the two Secret Service agents fired their weapons and neutralised the threat. He is deceased at the scene."

Members of the public with any information which could aid detectives have been urged to come forward by the FBI. Brett Skiles, the special agent in charge of the FBI's Miami field office, said: "If you live in the area of the shooting, please check your exterior cameras for last night, early this morning."

Mr Skiles added: "If you see anything that looks suspicious or out of place, please contact us... call FBI or contact the West Palm Beach Sheriff's Office." Skiles said the "evidence response team" is scouring the scene and will continue to work there "as long as it takes".