Rush Limbaugh says he knows who's out to get him -- only he won't say who.

Fresh out of rehab for his addiction to painkillers, the radio host revealed his suspicions about an ABC News report saying Limbaugh is being investigated for the money he used to buy prescription drugs.

"I know where this is coming from. I know who's behind it, and I know what the purpose of the story is," he said.

But that was as far as Limbaugh's declaration went.

ABC News said Tuesday that authorities are investigating whether Limbaugh skirted state money-laundering laws in getting money to buy OxyContin and other prescription painkillers.

Limbaugh, who is said to earn $35 million a year, reportedly made 30 to 40 cash withdrawals from his bank, U.S. Trust -- each just under $10,000. According to IRS rules, banks must report if anyone makes a single withdrawal of more than $10,000.

Authorities will determine in the coming weeks whether Limbaugh will face charges. A conviction in Florida would be a first-degree felony, carrying a maximum sentence of 30 years in prison. The Palm Beach County, Fla., state attorney's office reportedly has declined comment on ABC's report.

Limbaugh's lawyer, Roy Black, told ABC News: "There's no basis for these charges. He has not committed any acts of money laundering, and he absolutely denies it."

On the air Wednesday, Limbaugh reinforced his denial of doing anything illegal, but did say he had bank workers deliver cash to his office and radio studio. He termed this spending money for "travel, for food, for gratuities. I did that two or three times."

He also said U.S. Trust is "not a traditional bank." (On its Web site, U.S. Trust describes itself as "one of America's oldest investment management and trust companies ... Founded on Wall Street in 1853.")

Limbaugh claimed he used the money for some remodeling on his $24-million home in Palm Beach. "I was not laundering money," Limbaugh said. "I was withdrawing money, for crying out loud."

He also said U.S. Trust urged him to keep cash withdrawals under $10,000 so the financial institution could avoid federal paperwork necessary for such transactions.