The two sources, speaking on condition of anonymity because the talks are ongoing, stressed that the negotiations could collapse. In addition, no cases involving Arenas had been docketed in Superior Court by late Wednesday night. If the plea talks are not successful, a Superior Court grand jury would continue to hear evidence in the case.
Officials with the U.S. attorney's office in the District declined to comment about the case. Arenas's attorney, Kenneth L. Wainstein, also declined to comment.
The sources said it was unclear whether the plea agreement would set Arenas's punishment as probation, community service, a fine or some combination. But the negotiations would ensure that Arenas would not go to jail, one of the sources said.
If the grand jury were to charge Arenas, he likely would face charges of carrying a handgun without a license, which is a felony and punishable by up to five years behind bars. Because he has said he had four guns in the Verizon Center locker room, he could face up to 20 years in jail.
Prosecutors could bring their own charge of possessing an unregistered firearm, a misdemeanor that carries a 12-month sentence.
The guns became an issue after Arenas and Wizards teammate Javaris Crittenton got into an argument after a card game and Crittenton allegedly said he should shoot Arenas in his surgically repaired left knee, sources have said. Days later on Dec. 21, after a practice at Verizon Center, Arenas placed the guns on a chair next to Crittenton's locker with a note that said "pick one."
The grand jury began hearing testimony in the case on Jan. 5. Since Arenas met with law enforcement authorities, Wizards Coach Flip Saunders, team President Ernie Grunfeld and players Fabricio Oberto, Randy Foye, Caron Butler, Brendan Haywood, DeShawn Stevenson, JaVale McGee, Mike Miller and Andray Blatche have also spoken to authorities or the grand jury. Players Antawn Jamison, Mike James, Dominic McGuire, Earl Boykins and Nick Young say they have not been asked to be interviewed.
NBA Commissioner David Stern suspended Arenas indefinitely without pay Jan. 6.
An NBA official, on condition of anonymity, said league investigators met with many of the team's players this week. Union attorneys, including Billy Hunter, the head of the players' union, sat in on the interviews. The official added the NBA wants to conclude its investigation, which could result in further penalties to Arenas and some of his teammates, in the next week.
While at least three players testified to league officials they witnessed Crittenton chamber a round in his own gun, there are differences in their accounts. That, plus lack of proof that Crittenton took a weapon to the locker room, make it difficult for the NBA to severely punish the reserve guard, the official said.
The incident, which is also being investigated by the NBA, has cast doubt on the future of Arenas's career at a time when the 28-year-old guard was trying to regain his all-star form after missing the last two seasons following knee surgery.
The Wizards, who endorsed the suspension, have in the past week removed a banner with Arenas's image on it that covered part of the Sixth Street facade of Verizon Center, stopped displaying Arenas's No. 0 jersey and removed all references to him in the introductory video played before home games.
Arenas met Wednesday with Hunter to discuss his situation. Hunter said Tuesday he wanted to ensure that Arenas receives due process and doesn't want the punishment to exceed the transgression.
"You don't use a sledgehammer to drive a tack," Hunter said. "Right now, we're just waiting for the investigation to conclude and then we'll see what level or degree of discipline the commissioner is talking about imposing. And once the commissioner makes his decision, that will determine what extent we get involved and don't get involved."