A dispute that began on the team plane and resumed more than 24 hours later in the team's locker room between Washington Wizards guards Gilbert Arenas and Javaris Crittenton is at the center of an investigation by local and federal authorities into Arenas' recent admission of gun possession on Wizards property, according to sources close to the situation.

Multiple sources told ESPN.com that an argument commenced during a card game on the team's overnight flight back to Washington from Phoenix on Dec. 19 and escalated into a heated exchange between Arenas and Crittenton. The Wizards had Dec. 20 off, but sources say the hostilities resumed Dec. 21 in the locker room on a practice day.

Sources say that Arenas, in response to what was said on the flight, placed three guns he owns on a chair near Crittenton's locker stall and invited him to pick one before practice on Dec. 21. Sources said that Crittenton subsequently let Arenas know that he had his own gun.

The New York Post, quoting league security sources, reported in Friday's editions that Arenas and Crittenton pulled guns on each other over a gambling debt during the pre-practice confrontation at the Verizon Center.

The Washington Post, in a story posted on its Web site Friday night, quoted Arenas as saying, "That's not the real story." The newspaper also reported that the argument between Arenas and Crittenton was over "who had the bigger gun" and that there was never any intent to physically harm Crittenton, according to "a person who has spoken with Arenas recently."

It is not known how many other Wizards players were in the locker room at the time of the clash. The Wizards and Arenas have maintained since Dec. 24, when the team publicly confirmed that Arenas had stored three guns in a locked box in his locker, that the firearms were unloaded.

In an interview with the New York Daily News, Nets guard Devin Harris, a sixth-year veteran and 2009 All-Star, estimated that 60 to 75 percent of NBA players owned guns.

"I mean, look at the situation," said Harris, who told the newspaper he did not own a gun. "A lot of guys have been robbed. A couple of guys, God rest their souls, have passed away. I guess they feel like they need some sort of protection, I don't know. I can't speak for everybody."

If either Arenas or Crittenton is found to have brandished a gun against his teammate, long-term suspensions and heavy fines from NBA commissioner David Stern would appear to be likely, given the ever-rising levels of Stern's distaste for any hint of violence in the league in the wake of the infamous Indiana-Detroit brawl in November 2004.

The league office, though, is expected to wait to see whether local or federal charges are filed in the case before determining the scale of potential punishments.

Arenas spoke briefly with reporters Friday afternoon following Washington's practice and also made numerous statements via his Twitter account disputing the New York Post's report, which alleges that Crittenton became angry at Arenas for refusing to make good on a gambling debt, prompting Arenas to pull a gun first and Crittenton to respond by grabbing his own gun.

The Washington Post reported Friday afternoon that Arenas is threatening to sue the New York Post. The Washington Post also spoke to Arenas' father, Gilbert Arenas Sr., who said: "From the respect of guns being pulled in the locker room and at each other... that's ludicrous. Gilbert Jr. bringing the guns to the locker room to keep away from his kids, that's true. But Gil did not pull a gun on anybody. That's about all that I can say."

Arenas eventually turned his three guns in to team security and later told reporters—after a CBSSports.com report on Christmas Eve revealed that Arenas was being investigated for violating league rules on gun possession—that he brought them to the workplace because he no longer wanted them in his house after the birth of his third child in early December.

District of Columbia police officials immediately began looking into the matter and announced in a statement Wednesday, without naming any names or providing further details, that they have begun assisting the U.S. Attorney's Office in a joint probe into "an allegation that weapons were located inside a locker room at the Verizon Center."

Through a series of tweets, Arenas appeared Friday to be trying to downplay the severity of the situation in his usual glib manner. But the potential range of punishments would figure to be severe given the stricter-than-usual gun laws in the District of Columbia and the NBA's rules forbidding gun possession on league property.

Although no action from the league office is expected until the legal process plays out, which is the NBA norm, Stern is bound to take an especially dim view of the whole episode in deference to late Wizards owner Abe Pollin, who changed the team's nickname from Bullets to Wizards in 1997 in part because he was so profoundly affected by the assassination of former Israeli prime minister and close friend Yitzhak Rabin. Until his death in November, Pollin was as close to Stern as any NBA owner.

"There is an active investigation by D.C. law enforcement authorities, which we are monitoring closely," NBA spokesman Tim Frank said Friday. "We are not taking any independent action at this time."

The Wizards, in a statement issued Friday, said: "We take this situation and the ongoing investigation very seriously. We are continuing to cooperate fully with the proper authorities and the NBA and will have no further comment at this time."

In Friday's New York Post report, Wizards president Ernie Grunfeld is quoted as saying: "It's in the hands of the authorities. We're going to get to the bottom of this, if there is a bottom to this."

The controversy is the latest and possibly biggest setback in Washington's highly disappointing 10-20 start. Arenas is averaging 22.7 points and 6.9 assists after missing much of the past two seasons because of multiple surgeries on his left knee, but there is already considerable curiosity—not only in the media but among rival teams watching the drama unfold—whether the Wizards will eventually try to void the remainder of Arenas' mammoth six-year, $111 million contract because of this serious nature of this incident.

Arenas may not play Saturday against the San Antonio Spurs because of soreness in his left knee, Wizards head coach Flip Saunders told The Washington Post on Friday. Saunders would not comment on the reported dispute between Arenas and Crittenton.

Crittenton has not played all season because of an ankle injury and declined comment Friday when reached by the Washington Post. Crittenton's new agent, Mark Bartelstein, also declined comment Friday.