A three day manhunt that began Saturday when FBI agents raided a well-known political consultant's home, came to an end Monday evening when Ryan Chamberlain was spotted at Crissy Field.

A law enforcement source says two San Francisco police officers were on their regular patrol when they saw the white 2008 Nissan Altima in a parking lot. It was near the Beach Hut Cafe to the west of the St. Francisco Yacht Club lot. The officers checked the license plate and then approached the vehicle, ordering Chamberlain to get out of the car.

A driver for the rideshare company Uber told KTVU he had been taking a break when he heard the officers shouting. He took video of Chamberlain being taken into custody.

Ryan Kelly Chamberlain II, 42, on Monday afternoon shortly after announcing that they had found his car near Crissy Field, just south of the Golden Gate Bridge.

"I heard some commotion going on. Took a look out my window saw an arrest being made. Got out of my car and starting rolling film with my iPhone," said Morgan Manos, a San Francisco Uber driver.

Manos says that Chamberlain called out to him for help as officers took him away.

"The cop said back away. The guy who was getting arrested looked at me and said help," said Manos.

Chamberlain, 42, once worked with San Francisco's political elite. He was a social media consultant who had worked with Gavin Newsom and was well-known in the city's political circles.

He became the target of a manhunt Saturday after FBI agents raided his home near the intersection of Polk and Jackson streets. Officials say they found explosive devices in his apartment but Chamberlain had disappeared.

About 2 p.m. Monday, a tip led FBI agents to the Mad Dog in the Fog bar in San Francisco's Lower Haight neighborhood. The bartender said Chamberlain used his ATM card.

FBI agents followed the lead but Chamberlain was not there when they arrived.

Mike Burt, an employee at the nearby Toronado Bar across the street told KTVU, "There was a couple undercover officers with a picture, 3 pictures of the guy asking if anybody seen him."

At 6:22 p.m. the officers had located Chamberlain and arrested him. San Francisco police brought in the bomb squad. They used a robot to check the vehicle for explosives.

"I figured if there's a manhunt surely this guy's going to get out of the city. I didn't imagine I'd run into him down at the beach," said Manos.

Chamberlain is being held on federal charges of possessing explosives.

The FBI and police plan to have news conference Tuesday morning with more details.