Suspected gunman Cole Allen checked into the Hilton Hotel hosting the White House Correspondents' Dinner on Friday, just one day before the event, sources told Fox News.
Allen, 31, a computer scientist from Torrance, California, is accused of opening fire at the event where President Donald Trump was in attendance. Initial reports say Secret Service agents fired 3-4 shots, and Allen fired at least one.
The FBI is conducting a ballistics investigation at its lab in Quantico, and authorities are also working with credit card companies to go through purchases going back in time.
Authorities said Allen was initially talking with police, but he began refusing to speak as of Sunday morning.
Sources say Allen is scheduled for his initial court appearance sometime Monday.
Allen told law enforcement after his arrest Saturday night that he was targeting Trump administration officials, according to senior federal law enforcement sources.
Allen said he planned to "shoot Trump administration officials," the sources said.
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Authorities have said Allen rushed a Secret Service checkpoint at the event at the Washington Hilton while armed with multiple weapons. He allegedly then opened fire, striking a Secret Service officer in his ballistic vest.
Acting Attorney General Todd Blanche said on Sunday that authorities do not believe Allen worked with any accomplices. Trump said Saturday night that the shooter was a "lone wolf."
"Well, what President Trump said is that as of now we think that, that's what the police chief said as well," Blanche told NBC's "Meet the Press" on Sunday. "But this is an investigation that is 12 hours, 13 hours old, and so those facts can change, and they often do change. And if there's anybody else involved we will leave no stone unturned to find out everything we can about that."
"But from what we know right now, from what we know given what happened last night, and the evidence we've gathered so far, we don't believe anybody else was involved, but again, we have a lot of work left to do, and a lot of evidence left to go through and to collect," Blanche added.
Fox News' David Spunt contributed to this report.










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