A man who volunteered at a gay community centre had a box of ammunition with him when he said "I don't like your politics" and shot a security guard at the Washington, D.C., headquarters of a conservative U.S. lobbying group, authorities said Thursday.

Floyd Lee Corkins, II, was ordered held without bond on charges that he opened fire a day earlier inside the lobby of the Family Research Council, an influential conservative Christian group that has supported the president of the fast-food chain Chick-fil-A in his staunch opposition to same-sex marriage.

Corkins also had 15 Chick-fil-A sandwiches in his backpack, authorities said. It wasn't immediately clear what he planned to do with them.

The shooting was swiftly condemned by groups across the ideological spectrum, including President Barack Obama and his Republican challenger Mitt Romney. The attack also tapped into deep divisions over cultural issues like gay marriage and drew finger-pointing about whether inflamed rhetoric on either side was to blame.

Family Research Council President Tony Perkins said "reckless rhetoric" from organizations that disagree with his group's opposition to abortion and same-sex marriage was to blame for the shooting.

"Corkins was given a license to shoot an unarmed man by organizations like the Southern Poverty Law Center that have been reckless in labelling organizations hate groups because they disagree with them on public policy," Perkins said.

The Southern Poverty Law Center, which tracks and litigates hate groups, labelled the FRC as a hate group in 2010 for what it called the group's anti-gay stance.

Mark Potok, a senior fellow at the SPLC, called Perkins' accusation "outrageous." He said the council earned the designation for spreading false propaganda about the gay community, not for its opposition to same-sex marriage.

"The FRC routinely pushes out demonizing claims that gay people are child molesters and worse — claims that are provably false," he said in a statement. "It should stop the demonization and affirm the dignity of all people."

Guard wrestled gun away

Corkins, 28, who recently had been volunteering at a city community centre for lesbian, gay, bisexual and transgender people, told the guard words to the effect of, "I don't like your politics" and pulled a handgun from his backpack, according to an FBI affidavit.

The guard was shot in the arm but was able to help wrestle the gun away and restrain the shooter, police said.

Corkins, who lives with his parents, was charged with assault with intent to kill and bringing firearms across state and was ordered held pending a hearing next week. He told the judge he had only $300 in his account and was appointed a public defender. He was otherwise silent during the hearing and stared ahead impassively.

The Family Research Council had recently defended Chick-fil-A president Dan Cathy for his opposition to gay marriage. The council strongly opposes gay marriage and abortion and says it advocates "faith, family and freedom in public policy and public opinion." The conservative group maintains a powerful lobbying presence, testifying before Congress and reviewing legislation.

Corkins' parents told FBI agents that he has "strong opinions with respect to those he believes do not treat homosexuals in a fair manner," the complaint says.

The assault charge carries up to 30 years in prison and the weapons charge has a 10-year maximum sentence.

An open black box resembling a gun box was found in the passenger seat of Corkins' car, the affidavit says. Corkins used a Sig Sauer 9mm pistol that was legally bought and owned, said Richard Marianos, special agent in charge of the ATF's Washington field office.

The guard, Leonardo "Leo" Johnson, 46, was resting comfortably at a hospital Thursday. His mother, Virginia Johnson, said she had not been to visit him but had spoken to him by phone.

"He said he feels very well," she told The Associated Press in a brief interview. "I am proud of him, very proud of him."