(CBSNEWS) – Federal officials say they’ve arrested a man who they say was planning a terror attack on Christmas Day in San Francisco in support of the Islamic State of Iraq and Syria (ISIS), CBS News justice correspondent Paula Reid reports.

Everitt Aaron Jameson, 26, has been charged with providing material support for terrorism, according to federal court documents. Prosecutors say Jameson planned to detonate an explosive on the city’s Pier 39 on Christmas because he knew it would be heavily crowded. Jameson was born in Modesto, California, a DOJ official told Reid.

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An individual reported Jameson for suspicious activity on Facebook after he allegedly posted GIFs of attacks in the U.S. and the New York City attack that left 8 people dead in October, court documents say.

The FBI said it found a letter signed by Jameson in which he took credit for the planned attack. “You’ve Allowed Donald J Trump to give away Al Quds to the Jews,” the letter said, using the Arabic name for “Jerusalem.” Mr. Trump recently announced the U.S. will recognize Jerusalem as the capital of Israel.

Prosecutors say Jameson apparently wanted to detonate the explosives to funnel people into an area where he could inflict more casualties. The FBI executed a search warrant on his home on Dec. 20 and allegedly found multiple firearms and explosives materials.

Two days prior to the raid, an FBI employee accidently called Jameson’s cellphone number from a Washington, D.C., area code, court papers say. Jameson called the number back but the employee let it go to his voicemail, which identified his name but not that he was a federal agent.

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It appears that Jameson may have been clued-in that the feds were onto him. He soon told an undercover agent that “I also don’t think I can do this after all. I’ve reconsidered.”

In November, Jameson filled out a “Franchise Tow Truck Driving Application” with the Modesto Police Department, prosecutors said. The FBI investigation revealed that Jameson was previously discharged from the U.S. Marine Corps for failing to disclose his latent asthma. He attended basic recruit training and earned a sharpshooter rifle qualification. He was trained in both M16 and AK-47 rifles.

Attorney General Jeff Sessions applauded law enforcement officials in a statement Friday.

“Our incredible law enforcement officers have once again helped thwart an alleged plot to kill Americans. I want to thank the FBI agents and federal prosecutors and everyone else who helped make this possible,” Sessions said.

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