WASHINGTON — The investigation of Gilbert Arenas and the guns he brought to the Verizon Center took a much more serious turn yesterday amid a report that the Washington Wizards point guard and teammate Javaris Crittenton allegedly drew on each other during a locker-room argument over a gambling debt.

Arenas responded with a flurry of messages on Twitter, at times making light of the news but also making one tweet that read somewhat like a denial: "I understand this is serious..but if u ever met me you know i dont do serious things im a goof ball this story today dont sound goofy to me."

Arenas later tweeted he couldn't talk about the report the way he wanted to. He did not respond to a text message left by The Associated Press. A message left for Crittenton's agent also was not returned.

The NBA and the Wizards would only confirm that an investigation is taking place — and it's being led by law enforcement, not the league.

D.C. police said they are assisting the U.S. Attorney's Office in the matter. The Wizards said they are cooperating and they "take this situation and the ongoing investigation very seriously."

The Wizards and Arenas both have acknowledged that Arenas kept guns in his locker. The team has said the firearms were unloaded and kept in a locked container with no ammunition. Arenas has said he took his guns to the Verizon Center because he didn't want them in his house after the birth of his latest child. He said he later handed them over to team security to give to police.

"They just want to know where I got them from," Arenas said Tuesday night after a loss to the Oklahoma City Thunder. "They want to make sure they're not dirty guns."

But Yahoo! Sports and the New York Post, both citing unidentified sources, reported the investigation now involves Crittenton. The Post reported Crittenton became angry at Arenas for refusing to make good on a gambling debt. That prompted Arenas to draw on Crittenton, who then reached for a gun, league security sources told the Post.

The nation's capital has some of the most strict gun laws in the nation. The NBA's collective bargaining agreement allows for players to legally possess firearms, but prohibits them at league facilities or when traveling on league business.

Pending the outcome of the investigation, Arenas and Crittenton both could face fines or suspensions from the NBA. Commissioner David Stern has taken a strong stance on guns, saying in 2006: "We think this is an alarming subject, that although you'll read players saying how they feel safer with guns, in fact those guns actually make them less safe."

Arenas was suspended for Washington's season opener in 2004 because he failed to maintain proper registration of a handgun while living in California in 2003. Arenas, in the second season of a six-year, $111 million contract, formerly played for Golden State.

Arenas is averaging 22.7 points this season. Crittenton has an injured left foot and hasn't played this season.