The FBI said Sunday it was investigating “what appears to be an attempted assassination” of Donald Trump at his golf club in West Palm Beach, Florida, just nine weeks after the Republican presidential nominee survived another attempt on his life. Trump said he was safe and well.

Palm Beach County Sheriff Ric Bradshaw said the U.S. Secret Service agents fired at a man pointing an AK-style rifle with a scope into the club as Trump was on the course. Bradshaw said the gunman also had two backpacks hanging on a fence and a GoPro camera, and that he was about 400 yards to 500 yards away from Trump and hiding in shrubbery while the former president played golf on a nearby hole. The person dropped the weapon and fled in an SUV, and was later taken into custody in a neighboring county.

The incident was the latest jarring moment in a campaign year marked by unprecedented upheaval. It occurred roughly two months after Trump was shot during an assassination attempt at a rally in Pennsylvania, and a bullet grazed his ear. Only a week later, President Joe Biden withdrew from the race.

In an email to supporters, Trump said: “There were gunshots in my vicinity, but before rumors start spiraling out of control, I wanted you to hear this first: I AM SAFE AND WELL!”

“Nothing will slow me down. I will NEVER SURRENDER!” the former president said.

The golf course was partially shut down for Trump as he played, and agents were a few holes ahead of him when they noticed the person with the firearm, Bradshaw said. There are several areas around the perimeter of the property where golfers are visible from the fence line. Secret Service agents and officers in golf carts and on ATVs generally secure the area several holes ahead and behind Trump when he golfs. Agents also usually bring an armored vehicle onto the course to quickly shelter Trump should a threat arise.

Trump had returned to Florida this weekend from a West Coast swing that included a Friday night rally in Las Vegas and a Utah fundraiser. His campaign had not advised Trump’s plans for Sunday. He often spends the morning playing golf, before having lunch at the club, one of three he owns in the state.

The former president has had a stepped-up security footprint since the assassination attempt in July. When he has been at Trump Tower in New York, a lineup of dump trucks have parked in a wall outside the building. And at outdoor rallies, he now speaks from behind an enclosure of bulletproof glass.

Trump was returned safely after the incident to his private Mar-a-Lago club, where he resides in neighboring Palm Beach, according to a person familiar with the matter.

The White House said President Joe Biden and Vice President Kamala Harris, the Democratic presidential nominee, had both been briefed and would be kept updated on the investigation. The White House added they were “relieved” to know Trump is safe.

Harris, in a statement said she was “glad” Trump was safe, adding that “violence has no place in America.”

Martin County Sheriff William D. Snyder said the suspect was apprehended within minutes of the FBI, Secret Service and Palm Beach County Sheriff’s Office putting out a “very urgent BOLO” — or “be on the lookout” alert” detailing the specific vehicle sought, license plate number and occupant description.

Snyder said his deputies “immediately flooded” northbound I-95, deploying to every exit between the Palm Beach County line to the south and St. Lucie County line to the north.

“One of my road patrol units saw the vehicle, matched the tag and we set up on the vehicle,” Snyder said, “We pinched in on the car, got it safely stopped and got the driver in custody.”

Snyder told WPTV that the suspect “was not armed when we took him out of the car.”

The man had a calm, flat demeanor and showed little emotion when he was stopped by police, Snyder said, saying the suspect did not question why he was being pulled over.

“He never asked, ‘what is this about?’ Obviously, law enforcement with long rifles, blue lights, a lot going on. He never questioned it,” Snyder said.

Attorney General Merrick Garland has been briefed on the situation and is receiving regular updates about it, a Justice Department spokeswoman said.

WATCH: Sean Hannity speaks with Trump 3 times since incident, and had latest info:

Additionally, CNN is reporting that “Officials believe the shots fired at Trump International Golf Club were intended for former President Donald Trump.”

CNN: AK-47 & GoPro camera found at scene of shooting at Trump International Golf Club West Palm Beach