NEW YORK (CBSNewYork) – The FBI says a California man wanted to attack San Francisco’s popular Pier 39 on Christmas Day.

Web Extra: Read The Complaint (.pdf)

According to the FBI, Everitt Aaron Jameson, 26, told an undercover FBI agent Christmas Day was the “perfect day” for an attack on Fisherman’s Wharf.

Jameson, a tow truck driver who lives in Modesto, offered to make use of his vehicle.

Jameson allegedly believed he was working with ISIS, according to authorities.

“Jameson specifically named Pier 39 in San Francisco as a target location because he had been there before and knew that it was a heavily crowded area, and that, according to Jameson, no reconnaissance or site survey would be necessary (because Jameson already was familiar with the area). Jameson explained that he also desired to use explosives,” prosecutors allege in the complaint. “Jameson said he did not have and did not need an escape plan because he was ready to die.”

As CBS2’s Jessica Layton reported, the popular tourist spot would have been packed on Monday.

“This would have been probably the biggest attack since 9/11 in terms of casualties and carnage,” security expert Manny Gomez said.

The investigation may have been inadvertently exposed when an FBI employee mistakenly called Jameson’s cell phone using a phone number with a Washington, D.C. area code. After the call, Jameson apparently suspected he was under surveillance and wrote to the undercover operative “I also don’t think I can do this after all. I’ve reconsidered.”

Authorities then carried out a search warrant of his home, where they found a handwritten note.

“You all have brought this upon yourselves,” the note said. “You’ve allowed Donald J. Trump to give away [Jerusalem] to the Jews. Both you and he are wrong, it belongs to the [Muslims].”

They also said they found guns and a will.

As former FBI agent Manny Gomez explained, the suspect does not fit the usual profile of a terrorist.

“This person is American. He served in the military, trained in the military. He’s one of us, but he’s not,” he said.

Jameson was discharged from the U.S. Marines for fraudulent enlistment, according to court documents.

Court documents allege that Jameson “voiced support for the October 31, 2017 terror attack in New York City.” Eight people were killed in that attack.

His father said the picture of the evil person emerging in the news is not the man they knew.

“Loss of words. I don’t know what to say,” he said, “That’s just, that’s just not him.”

An informant noticed that Jameson began to show signs of radicalization after being discharged. He ‘liked’ and ‘loved’ pro-terrorism Facebook posts.

NYPD BOOSTS SECURITY FOR CHRISTMAS

The NYPD had already announced it was stepping up security around churches for Christmas Eve and Christmas Day, but added that it was not doing so in response to any specific threat.

There will be blocker trucks and officers armed with heavy weapons outside St. Patrick’s Cathedral.

“Obviously, Christmas coming up this weekend, Christmas Masses. We’re going to have full counter-terrorism overlays at St. Pat’s, there will be blocker cars, there will be teams out there. We will have truck restrictions on both Fifth and Madison Avenues from 42nd Street up to 57th Street,” said NYPD Chief of Patrol Terence Monahan. ”

“We will have heavy weapons teams responding throughout the city and throughout Midnight Masses and through the Masses on Christmas Day as well,” Monahan said.

The increased police presence come ahead of the New Year’s Eve celebration in Times Square celebration.