The gunman opened fire with a pistol on Friday in the Backstreet Cafe in Roanoke, Virginia, witnesses said.
The accused man, Ronald Gay, is said to have told police he was fed up with people making jokes about his surname.
The gunman opened fire with a pistol on Friday in the Backstreet Cafe in Roanoke, Virginia, witnesses said.
A bar patron - Danny Lee Overstreet, 43 - was killed, and six other people were injured in the shooting. Two of the injured remained in hospital on Monday, one in a critical condition.
If any other victims die, the charges against Mr Gay, 54, could be upgraded so that he faces the death sentence.
Confession
According to police, Mr Gay confessed to the shootings shortly after the attack.
"He said he was shooting people to get rid of, in his term, 'faggots,'" Lieutenant William Althoff of the Roanoke police was quoted as saying.
Mr Gay, a drifter from Florida, had allegedly asked people at a Roanoke restaurant for directions to a gay bar. Restaurant workers initially thought he was joking, then called police after he showed them a gun.
The shooting occurred minutes later.
Mr Gay faces a maximum sentence of life imprisonment on the first-degree murder charge.
Vigil
According to police, Mr Gay said he had long resented comments about his name, and he said some of his children had changed their last name because of persistent teasing.
"The guy was standing there with a trench coat on, and the gun was going pop, pop, pop, pop, pop, and people were falling over everywhere, trying to get behind booths.
"He just stood there for a couple of seconds, then lowered the gun and walked out like nothing had happened," she told Reuters news agency.
'Vietnam trauma'
The alleged gunman's brother William said Ronald Gay was a Vietnam veteran suffering from post-traumatic stress disorder.
Mr Gay had been seeking treatment from a nearby hospital, his brother said.