The National Basketball Players Association announced Friday that embattled union chief Billy Hunter has been placed on indefinite leave of absence.

Longtime union lawyer Ron Klempner was appointed acting executive director of the union until every member of the union "can have a vote in the matter," the NBPA said.

Hunter was notified of the decision Friday morning, sources said.

"This organization has been disrupted and we will no longer tolerate it. Immediate action was necessary and taken to protect you," union president Derek Fisher said in a memo circulated to players Friday.

Hunter's attorney responded that the actions weren't allowable under NBPA rules, setting up the possibility of a Hunter fight to keep his job.

The NBPA announced that it has formed an interim executive committee and advisory committee "to move the organization forward" in the wake of a damaging report by the independent firm of Paul, Weiss, Rifkind, Wharton & Garrison LLP, which was hired to look into the union's business practices under Hunter's leadership. The interim executive committee will consist of the five active members of the most recent executive board, according to union bylaws.

The report last month found no evidence of illegal use of union funds, but revealed that Hunter withheld knowledge that his contract was never properly approved, used poor judgment with his hiring practices and spent improperly on travel and gifts.

The NBPA also will hire outside lawyers to assist it leading into a pivotal set of meetings scheduled for All-Star Weekend in Houston later this month and will consider moving meetings to a different date on the calendar to "ensure that all players will have the best chance to attend without conflict."

Hunter's attorney, Thomas Ashley, said his client had been treated unfairly and already had taken steps to improve the union.

"I am deeply troubled by the lack of fundamental fairness shown my client by a group whose authority to take such action is highly questionable. The act of placing my client on administrative leave is not supported in either the constitution or bylaws of the NBPA," Ashley said. "Furthermore, Mr. Hunter was not given any opportunity to respond to the Paul, Weiss report prior to the time that a decision was made to place him on administrative leave."

Hunter has headed the union since 1996. The review was sought in part by Fisher, who clashed with Hunter during and after the NBA lockout that lasted from July 2011 to November 2011.

Agents were angry with Hunter's strategies, though he has remained popular and respected by many players.

Because Hunter's contract -- worth $3 million a year, signed in 2010 and was to run through either 2015 or 2017 -- was never properly approved, the report found that players were under no obligation to keep him.

According to the report, Hunter was aware by at least November 2011 that the executive committee and player representatives had not approved the deal according to union bylaws.

In a statement released Friday, Fisher said that because of the ongoing investigations being conducted by the U.S. Department of Labor and the U.S. attorney's office, players wanted the executive committee to take steps to protect them.