The White House Correspondents' Dinner suspect sent a "manifesto" to his family. CBS News reviewed what's in it.

The White House Correspondents' Dinner shooting suspect wrote a "manifesto" that stated he planned to target Trump administration officials, "prioritized from highest-ranking to lowest," according to a copy obtained by CBS News. 

Cole Allen, 31, wrote that law enforcement, hotel employees and guests weren't his intended targets but that he would still attack them to get to the administration, adding: "I really hope it doesn't come to that."

Allen charged a security checkpoint outside the dinner, armed with a shotgun, a handgun and knives, acting Attorney General Todd Blanche said. Mr. Trump and other administration officials were quickly escorted out of the event, which was canceled shortly thereafter. 

Law enforcement sources told CBS News that Allen's brother, alarmed by the email he and other family members received, called police in Connecticut to alert them Saturday night.

Authorities said they found other writings at his home in Torrance, California, and in his 10th-floor hotel room at the Washington Hilton Hotel, where the dinner was being held.

"I may have given a lot of people a surprise today"

Throughout the email, his tone was matter-of-fact, and at times ironic. "Hello everybody!" Allen wrote. "So I may have given a lot of people a surprise today."

"I apologize to my parents for saying I had an interview without specifying it was for 'Most Wanted,'" he wrote.

He also apologized to colleagues and his students for telling them he had a personal emergency, and said he expected that by the time anyone read the email, he probably would need emergency care, referring to any potential injuries as "self-inflicted status."

Officials "prioritized from highest-ranking to lowest" — except one

Allen said he planned to carry out the attack because he didn't want the "crimes" of the administration to "coat [his] hands." He didn't refer to Mr. Trump or the event by name, but said he intended to target administration officials "prioritized from highest-ranking to lowest." 

But "not including Mr. Patel," he said, referencing the FBI director who was also at Saturday's dinner.

He said that he wouldn't target Secret Service, Capitol Police or National Guard troops unless necessary. "I hope they are wearing body armor," he wrote. A Secret Service officer who was shot was wearing a bulletproof vest and was released from the hospital Sunday. 

Allen wrote: "In order to minimize casualties, I will also be using buckshot rather than slugs (less penetration through walls)."

Rebuttals to hypothetical objections

Allen's writing addressed a series of objections that his readers might have had, with "rebuttals" for each.

"As a half-black, half-white person, you shouldn't be the one doing this," he wrote as one hypothetical objection to carrying out the attack. "Rebuttal: I don't see anyone else picking up the slack."

Another hypothetical objection Allen raised in the email was that as a Christian, he should "turn the other cheek."

"Rebuttal," he wrote. "Turning the other cheek is for when you yourself are oppressed." He then went on to list several anonymous hypothetical victims who have experienced hardship, and in some cases he blamed the administration for those hardships. 

"I don't expect forgiveness, but if I could have seen any other way to get this close, I would have taken it," he said, referencing the dinner.

Allen criticizes security at hotel

"PS," he continued, "Ok now that all the sappy stuff is done, what the hell is the Secret Service doing? … No damn security. Not in transport. Not in the hotel. Not in the event." 

He said that if he had been an Iranian agent, he could have brought in a machine gun, which he referred to as "Ma Deuce," and no one would have noticed. 

Because the Washington Hilton remained a functioning hotel with numerous public spaces during the dinner, the entire building wasn't secured by the Secret Service, just the specific areas where the dinner was held.

Family says he referenced plans to do "something" to fix issues

After the attempted attack, Allen's sister told investigators that he often used "radical" rhetoric, sometimes talking about doing "something" to fix perceived problems in society, federal law and White House officials told CBS News. 

More than 2,500 people attended Saturday's gala, which celebrates the First Amendment. Mr. Trump has declined his invitation each year as president except this one. Mr. Trump has said he wants to reschedule the dinner within the next 30 days.