Washington (CNN) -- The suspect in Wednesday's shooting of a building manager at the headquarters of a conservative Christian group was charged Thursday with assault with intent to kill, ordered to undergo a mental health evaluation and held without bond.
In his initial appearance in U.S. District Court, Floyd Lee Corkins II, 28, also was charged with interstate transportation of a firearm and ammunition.
The assault charge is a District of Columbia offense that carries a maximum 30-year sentence. The federal firearms charge carries a 10-year maximum sentence.
At about 11 a.m., Corkins entered the Washington office of the Family Research Council, where he encountered the building manager, Leo Johnson, at the front door, according to a criminal complaint that cited a witness. Corkins "stated words to the effect of, 'I don't like your politics,' " the witness told FBI agents, according to the complaint.
Surveillance video shows that Corkins took a firearm from his backpack and shot Johnson in the arm, at which point the wounded Johnson "wrestled the firearm away from Corkins, and subdued him," according to the complaint.
Corkins, who was wearing a white plastic jumpsuit during Thursday's court appearance, was ordered to remain in custody pending a prelimary and detention hearing on August 24. His right eye was red and appeared swollen.
Magistrate Judge Alan Kay appointed a public defender after Corkins told him he had only $300 and could not afford to hire his own lawyer.
A law enforcement official told CNN that initial evidence indicated Corkins was acting alone.
Officials recovered a loaded Sig Sauer 9mm pistol and two additional loaded 9mm magazines, according to the complaint.
Inside the backpack, police found 50 rounds of 9mm ammunition and 15 Chick-fil-A sandwiches, the complaint says.
Family Research Council President Tony Perkins said the Chick-fil-A company gave the Family Research Council $1,000 "a number of years ago" but does not underwrite his group.
And the Family Research Council, which which focuses on family and anti-abortion issues and religious liberties, supported Chick-fil-A President Dan Cathy after he said in an interview published last month that his company is "a family-owned business, a family-led business, and we are married to our first wives. We give God thanks for that."
The statement sparked an uproar, with activists saying that Cathy voiced opposition to gay marriages.
"The Chick-fil-A culture and service tradition in our restaurants is to treat every person with honor, dignity and respect -- regardless of their belief, race, creed, sexual orientation or gender," the company says in a posting on its website.
Corkins "has strong opinions with respect to those he believes do not treat homosexuals in a fair manner," authorities said in the complaint, citing information from the suspect's parents, with whom he lives in Herndon, Virginia, outside Washington.
In an interview with CNN affiliate WJLA, Johnson said Corkins told him he was there to interview for an internship, then shot him without warning.
Johnson said it was after he had wrestled Corkins to the ground that the suspect told him the shooting was about the group's policies, according to WJLA.
Authorities found what appeared to be an open gun box on the seat of his car, which had been parked at the East Falls Church Metro station, according to the complaint.
Corkins legally purchased the handgun from a gun shop in Virginia within the last week, according to a law enforcement official.
Corkins had volunteered at the DC Center for the LGBT Community, a source working with the center told CNN. The group provides services and support to lesbian, gay, bisexual and transgender people,
He received a master's degree from George Mason University's College of Education and Human Development in 2006, the university said.
Family Research Council President Perkins told reporters Thursday that Johnson has a secondary role as a security guard, but that he was unarmed and did not wear a uniform.
Perkins said that he was with the wounded building operations manager when the man came out of surgery about midnight.
"I said, 'Leo, I want you to know that you're a hero.' "
"He said, 'Wow, this hero business is hard work.' So, he did not lose his sense of humor."
Perkins predicted Johnson would return to work soon.
While D.C. Police Chief Cathy Lanier and others have hailed Johnson as a hero, WJLA reported the 46-year-old told the station in a telephone interview that he was simply doing his job and is not comfortable being described as a hero.
He told the station that Corkins spoke with him after he was apprehended. "He said it wasn't about me," Johnson said. "It was about the organization."
Johnson's mother, Virginia Johnson, told the station her son is always trying to help people.
"I think it's wonderful, wonderful," she said of his actions.
White House spokesman Jay Carney declined to say whether the White House considers the attack a hate crime, but said President Barack Obama "firmly believes that violence of that kind has no place in our society."
Presumptive Republican presidential nominee Mitt Romney used nearly identical language in decrying the attack on Wednesday.
"There is no place for such violence in our society," he said in a statement. "My prayers go out to the wounded security guard and his family, as well as all the people at the Family Research Council whose sense of security has been shattered by today's horrific events."
CNN's Greg Seaby, Javi Morgado, Paul Courson, Sandra Endo, Mike M. Ahlers and Dan Gilgoff contributed to this report.