PHOENIX -- Former U.S. Senator George Mitchell said on Wednesday that investigators for his committee reviewing the use of performance-enhancing drugs in Major League Baseball have taken their case to Spring Training.

"I can confirm that members of my investigative staff have been, and will be, conducting interviews during Spring Training of various individuals who are involved in baseball," Mitchell said in a statement. "Our interviews are being conducted in both Arizona and Florida."

At the quarterly owners meetings here last month, Mitchell was invited by Commissioner Bud Selig to report his progress toward finishing a much-awaited report. The committee was formed almost a year ago to look into allegations that some of baseball's biggest current and former stars, including Barry Bonds, Mark McGwire, Sammy Sosa and Rafael Palmeiro, had used steroids during the course of their careers.

Mitchell told the owners that he had received less than stellar cooperation from their group and none at all from the players. At the time, he suggested that Congress could launch its own investigation if he ultimately produced an unsatisfactory report.

Mitchell said on Wednesday that the teams all being in camp gives his committee the opportunity to conduct a number of interviews at a quicker pace.

"The interviews are being conducted at this time because a number of witnesses are together in one place and the Spring Training sites for the Major League clubs are close together," Mitchell said. "It has been and continues to be my practice not to comment on the details of the investigation. We will answer as many questions as possible in our final report."

Selig commissioned Mitchell to spearhead the investigation just after the release of the book, "Game of Shadows," which documented the alleged exploits of such players as Bonds, Jason Giambi and Gary Sheffield, regarding their use of performance-enhancing substances largely during the period of 1998-2002.

Late last March, in establishing the investigation, Selig charged Mitchell with leaving "no stone unturned" when it came to discovering just what happened during those years and even earlier if the path led Mitchell in that direction.

Since then, Mitchell has had no help from the Players Association and not one player has aided in the investigation, fearing that any remarks made to the committee could be subpoenaed by the federal government in its ongoing case involving the seizure of data and records from the Bay Area Laboratory Co-Operative (BALCO) in 2003. Five people have been indicted in the scandal, and Bonds is currently under investigation for possibly committing perjury before a grand jury about his steroid use.

There's also been some resistance from ownership about complying with Mitchell's committee, which has no subpoena power and can't compel anyone to testify or turn over documentary information.

Under pressure from Congress, MLB instituted drug testing at the Major League level in 2003 and re-opened the Basic Agreement twice to strengthen the penalties for use of performance-enhancing drugs, even adding amphetamines to the testing and penalty schedule last year.

In the meantime, documented steroid use at the big-league level has become almost infinitesimal, down from the 5-to-7 percent of players who tested positive in 2003. Last season, no player on the 25-man roster of the 30 teams tested positive. It was announced after the postseason that Mets reliever Guillermo Mota had tested positive and he will be suspended the requisite 50 games to open the 2007 season.