Huntsville, Ala. ? A man looking for work opened fire Tuesday at a temporary employment agency during an argument about a CD player, killing four fellow job-seekers and wounding a fifth, police said.

Emanuel Burl Patterson later surrendered after a standoff at his apartment, where police tracked him down using the address he put on his job applications. Authorities turned off the building’s electricity while the temperature was near freezing. Police said the man shot at officers early in the standoff.

The shooting with a 9 mm semiautomatic handgun started about 6:30 a.m. in the lobby of Labor Ready Inc., where as many as 15 people were waiting for work.

“A fight broke out among two groups of men over a CD player,” said police spokesman Wendell Johnson. He said Patterson, 23, of Huntsville, regularly went to the office looking for work and was well known both to employees and other laborers.

“People who know him say he is a very unstable individual,” Johnson said without elaboration.

Michael Tucker Jr. said his father was in the office and told him the argument “was all over something about CDs and $20. There was some guys picking at (the gunman) and pushing him, laughing at him. They pushed him into a corner.”

Police respond to the Labor Ready Inc. temporary employment agency in Huntsville, Ala., after five people were shot. The shootings Tuesday, which left four people dead, occurred during an argument over a compact disc player.

According to police and witnesses, the gunman shot to death Billy Knox Jr., 22, and his father, Billy Knox Sr., 61, both of Huntsville, inside the building, then turned the gun on others.

Police said Benjamin Ferguson, 47, of Huntsville and David Seiler, 46, a Tennessee man whose hometown was not immediately available, were shot on the front steps. Seiler died during surgery, and the others were dead at the scene.

A fifth man, Royce Henderson, 46, of Huntsville, was shot in the leg and survived.

The gunman drove off after the shooting.

No charges were filed immediately against Patterson, but Madison County Dist. Atty. Tim Morgan said capital murder charges were likely.