Washington • International tax evaders who come clean will be able to avoid jail and pay reduced fines under a voluntary disclosure program announced Tuesday by the Internal Revenue Service.

Tax cheats will have until Aug. 31 to settle up with the IRS or face an ongoing crackdown against Americans who hide assets overseas, IRS Commissioner Doug Shulman said.

"If we find you, you face harsher penalties and the possibility of jail time," Shulman said. "If you come in voluntarily, you pay a steep price but avoid going to jail."

The offer is similar to one the IRS made in 2009 that netted 15,000 tax evaders. Shulman said the IRS has closed 2,000 of those cases, collecting $400 million in additional revenue.

Shulman said the new offer isn't as generous because he doesn't want to reward tax cheats who waited two years to come forward.

Under the new program, tax evaders must pay back taxes, interest and delinquency penalties for the past eight years, if accounts have been held that long. In addition, they will have to pay a penalty of up to 25 percent of the highest annual amount in the overseas account from 2003 through 2010.

Shulman said the 2009 disclosure program provided the IRS with many leads on the bankers and financial advisers who help Americans hide assets.

"We've been getting better and better at detecting offshore accounts. Therefore, the risk of being caught is increasing," Shulman said. "We now have a number of other banks under investigation based on information we received from our first round of disclosures and from other sources. Tax secrecy continues to erode."

The IRS long has had a policy that certain tax evaders who come forward before they are contacted by the agency usually can avoid jail time as long as they agree to pay back taxes, interest and hefty penalties.